[
  {
    "id": "3d-spirograph-nebula-title",
    "name": "3d-spirograph-nebula",
    "title": "🌀 3D Spirograph Nebula",
    "description": "A true 3D spirograph: torus knots, quantum roses and harmonograph spiros woven into space with perspective, additive glow, phosphor trails, echo interference, an orbiting starfield, gesture orbit and.",
    "category": "Interactive Art & Living Worlds",
    "file": "3d-spirograph-nebula.html",
    "path": "cards/3d-spirograph-nebula.html"
  },
  {
    "id": "a1c-average-glucose-converter-title",
    "name": "a1c-average-glucose-converter",
    "title": "🩸 HbA1c ⇄ Average Glucose",
    "description": "Convert HbA1c (%) to estimated average glucose with the NGSP/DCCT formula (eAG mg/dL = 28.7 × A1c − 46.7). Educational only — lab methods differ (IFCC mmol/mol vs NGSP %), and this is not a diagnosis.",
    "category": "Health & Fitness",
    "file": "a1c-average-glucose-converter.html",
    "path": "cards/a1c-average-glucose-converter.html"
  },
  {
    "id": "ab-test-significance-calculator-title",
    "name": "ab-test-significance-calculator",
    "title": "🧪 Split Test Lab",
    "description": "The two numbers every experiment platform charges you to see: is this difference real, and how long must the test run? Frequentist z-test with confidence intervals, a proper sample-size and duratio...",
    "category": "SaaS & Business Killers",
    "file": "ab-test-significance-calculator.html",
    "path": "cards/ab-test-significance-calculator.html"
  },
  {
    "id": "abv-proof-dilution-calculator-title",
    "name": "abv-proof-dilution-calculator",
    "title": "🥃 ABV, Proof & Dilution",
    "description": "US proof is 2 × ABV%. UK/EU labels use ABV%. Dilute with C₁V₁ = C₂V₂ (alcohol volume conserved). Mixing two bottles uses a weighted average. Not a drink-driving tool.",
    "category": "Culinary & Food Science",
    "file": "abv-proof-dilution-calculator.html",
    "path": "cards/abv-proof-dilution-calculator.html"
  },
  {
    "id": "accessible-text-prep-title",
    "name": "accessible-text-prep",
    "title": "♿ Accessible Text Prep",
    "description": "Paste something you need a specific person to understand — a letter from a council, instructions for an elderly relative, a form your colleague keeps skipping. This rewrites the presentation and th...",
    "category": "Wellbeing & Community",
    "file": "accessible-text-prep.html",
    "path": "cards/accessible-text-prep.html"
  },
  {
    "id": "acoustic-levitation-standing-wave-title",
    "name": "acoustic-levitation-standing-wave",
    "title": "🔊 Ultrasonic Acoustic Levitation",
    "description": "40 kHz ultrasonic standing wave acoustic trap. Non-contact levitation of micro-beads and liquid droplets suspended in mid-air at acoustic pressure nodes.",
    "category": "Science & Engineering",
    "file": "acoustic-levitation-standing-wave.html",
    "path": "cards/acoustic-levitation-standing-wave.html"
  },
  {
    "id": "acres-hectares-sqm-converter-title",
    "name": "acres-hectares-sqm-converter",
    "title": "🌾 Acres ⇄ Hectares ⇄ m²",
    "description": "International acre is exactly 4,046.8564224 m²; a hectare is 10,000 m² (a 100 m square). UK land ads mix acres and hectares. Edit any field.",
    "category": "Science & Engineering",
    "file": "acres-hectares-sqm-converter.html",
    "path": "cards/acres-hectares-sqm-converter.html"
  },
  {
    "id": "acupressure-somatic-point-map-title",
    "name": "acupressure-somatic-point-map",
    "title": "💆 Acupressure Point Relief Map",
    "description": "Non-invasive somatic reflexology locator. Guides precise anatomical pressure points for rapid drug-free relief of headaches, nausea, anxiety, and cramps.",
    "category": "Natural Remedies & Herbs",
    "file": "acupressure-somatic-point-map.html",
    "path": "cards/acupressure-somatic-point-map.html"
  },
  {
    "id": "adaptogen-matcher-matrix-title",
    "name": "adaptogen-matcher-matrix",
    "title": "🌱 Adaptogen Synergy Matcher",
    "description": "HPA-axis endocrine matching engine. Aligns clinical botanical adaptogens to your stress phenotype (high nighttime cortisol vs chronic adrenal exhaustion).",
    "category": "Natural Remedies & Herbs",
    "file": "adaptogen-matcher-matrix.html",
    "path": "cards/adaptogen-matcher-matrix.html"
  },
  {
    "id": "adulting-score-title",
    "name": "adulting-score",
    "title": "🏠 Adulting Score Calculator",
    "description": "How well are you really adulting? Take this brutally honest assessment and find out.",
    "category": "Productivity & Lifestyle",
    "file": "adulting-score.html",
    "path": "cards/adulting-score.html"
  },
  {
    "id": "age-calculator-exact-days-title",
    "name": "age-calculator-exact-days",
    "title": "🎂 Exact Age Calculator (Years, Months, Days)",
    "description": "Work out your exact age — or the time between any two dates — in years, months, weeks, days, hours, minutes and seconds. Shows your next birthday countdown, the weekday you were born, your zodiac s...",
    "category": "Mathematics",
    "file": "age-calculator-exact-days.html",
    "path": "cards/age-calculator-exact-days.html"
  },
  {
    "id": "age-calculator-exact-title",
    "name": "age-calculator-exact",
    "title": "🎂 Exact Age Calculator",
    "description": "Get your exact age in years, months, days and hours, plus the weekday you were born, your next birthday countdown and Western zodiac. Uses this device’s clock only — nothing is sent anywhere.",
    "category": "Mathematics",
    "file": "age-calculator-exact.html",
    "path": "cards/age-calculator-exact.html"
  },
  {
    "id": "age-calculator-title",
    "name": "age-calculator",
    "title": "🎂 Age Calculator",
    "description": "Your exact age in years, months and days — plus total days lived, next birthday countdown and 10,000-day milestones.",
    "category": "Mathematics",
    "file": "age-calculator.html",
    "path": "cards/age-calculator.html"
  },
  {
    "id": "ai-agent-react-loop-simulator-title",
    "name": "ai-agent-react-loop-simulator",
    "title": "🔄 AI Agent ReAct Loop Studio",
    "description": "Autonomous agent execution cycle simulator (Yao et al., Princeton). Visualizes Thought $\\to$ Action $\\to$ Observation state transitions and recursion limit safeguards.",
    "category": "AI & Autonomous Agents",
    "file": "ai-agent-react-loop-simulator.html",
    "path": "cards/ai-agent-react-loop-simulator.html"
  },
  {
    "id": "ai-chain-of-thought-scratchpad-title",
    "name": "ai-chain-of-thought-scratchpad",
    "title": "🧠 AI Chain-of-Thought Parser",
    "description": "Reasoning token extractor for o1, o3, DeepSeek-R1, and Claude Extended Thinking. Separates internal scratchpad reasoning from client-facing output and detects cognitive self-corrections.",
    "category": "AI & Autonomous Agents",
    "file": "ai-chain-of-thought-scratchpad.html",
    "path": "cards/ai-chain-of-thought-scratchpad.html"
  },
  {
    "id": "ai-context-window-budget-calc-title",
    "name": "ai-context-window-budget-calc",
    "title": "📊 AI Context Window Budget Lab",
    "description": "LLM token budget architect. Allocates context capacity across system prompt, RAG retrieval chunks, few-shots, conversation history, and reasoning tokens to prevent catastrophic truncation.",
    "category": "AI & Autonomous Agents",
    "file": "ai-context-window-budget-calc.html",
    "path": "cards/ai-context-window-budget-calc.html"
  },
  {
    "id": "ai-few-shot-prompt-synthesizer-title",
    "name": "ai-few-shot-prompt-synthesizer",
    "title": "⚡ AI Few-Shot Prompt Builder",
    "description": "In-context learning exemplar synthesizer. Enforces structured framing (XML tags vs JSON vs Markdown) and validates class distribution balance to prevent majority label bias.",
    "category": "AI & Autonomous Agents",
    "file": "ai-few-shot-prompt-synthesizer.html",
    "path": "cards/ai-few-shot-prompt-synthesizer.html"
  },
  {
    "id": "ai-function-call-schema-validator-title",
    "name": "ai-function-call-schema-validator",
    "title": "🤖 AI Function Calling Validator",
    "description": "Validate LLM tool-calling declarations against JSON Schema (OpenAI, Anthropic & Gemini). Tests simulated model payloads, identifies missing required fields, and detects type mismatches.",
    "category": "AI & Autonomous Agents",
    "file": "ai-function-call-schema-validator.html",
    "path": "cards/ai-function-call-schema-validator.html"
  },
  {
    "id": "ai-hallucination-entropy-gauge-title",
    "name": "ai-hallucination-entropy-gauge",
    "title": "🔍 AI Hallucination & Fact Check",
    "description": "Contextual grounding and hallucination risk evaluator for RAG pipelines. Pinpoints unverified entities, phantom dates, numbers, and ungrounded lexical assertions.",
    "category": "AI & Autonomous Agents",
    "file": "ai-hallucination-entropy-gauge.html",
    "path": "cards/ai-hallucination-entropy-gauge.html"
  },
  {
    "id": "ai-mcp-protocol-tool-tester-title",
    "name": "ai-mcp-protocol-tool-tester",
    "title": "🔌 AI MCP Tool Protocol Inspector",
    "description": "Model Context Protocol (MCP) JSON-RPC 2.0 inspector and mock runner. Validates protocol compliance for Anthropic and open-agent tool calling servers.",
    "category": "AI & Autonomous Agents",
    "file": "ai-mcp-protocol-tool-tester.html",
    "path": "cards/ai-mcp-protocol-tool-tester.html"
  },
  {
    "id": "ai-model-cost-latency-matrix-title",
    "name": "ai-model-cost-latency-matrix",
    "title": "💰 AI Model Cost & Speed Matrix",
    "description": "Comprehensive LLM economics & inference latency evaluator. Computes monthly token costs, prompt-caching savings, and tokens-per-second throughput across frontier and open-weight models.",
    "category": "AI & Autonomous Agents",
    "file": "ai-model-cost-latency-matrix.html",
    "path": "cards/ai-model-cost-latency-matrix.html"
  },
  {
    "id": "ai-prompt-injection-defense-lab-title",
    "name": "ai-prompt-injection-defense-lab",
    "title": "🛡️ AI Prompt Injection Defense",
    "description": "LLM adversarial attack analyzer. Tests agent prompts against prompt injections, delimiter hijacking, and jailbreaks, and auto-generates hardened XML containment wrappers.",
    "category": "AI & Autonomous Agents",
    "file": "ai-prompt-injection-defense-lab.html",
    "path": "cards/ai-prompt-injection-defense-lab.html"
  },
  {
    "id": "ai-toolbox-title",
    "name": "ai-toolbox",
    "title": "🤖 AI Toolbox Generator",
    "description": "Build your own custom AI tools by combining different AI capabilities. Create, save, and share personalized mini-tools in minutes! ✨ No coding required - drag, drop, and customize!",
    "category": "Productivity & Lifestyle",
    "file": "ai-toolbox.html",
    "path": "cards/ai-toolbox.html"
  },
  {
    "id": "ai-vector-embedding-similarity-title",
    "name": "ai-vector-embedding-similarity",
    "title": "📐 AI Vector Similarity Matrix",
    "description": "RAG & vector database embedding distance engine. Computes Cosine Similarity, Euclidean $L_2$, Dot Product, and Angular separation across semantic embeddings.",
    "category": "AI & Autonomous Agents",
    "file": "ai-vector-embedding-similarity.html",
    "path": "cards/ai-vector-embedding-similarity.html"
  },
  {
    "id": "air-fryer-oven-conversion-title",
    "name": "air-fryer-oven-conversion",
    "title": "🌬️ Air Fryer ⇄ Oven Converter",
    "description": "Turn a conventional-oven recipe into an air-fryer starting point: typically 20°C cooler and about 20% less time. Always check food, especially poultry, with a thermometer — baskets cook faster at t...",
    "category": "Culinary & Food Science",
    "file": "air-fryer-oven-conversion.html",
    "path": "cards/air-fryer-oven-conversion.html"
  },
  {
    "id": "airmass-extinction-calculator-title",
    "name": "airmass-extinction-calculator",
    "title": "🌫️ Airmass & Extinction Calculator",
    "description": "How much of a star's light the atmosphere is stealing at any altitude, in which band, and how long you have before it is not worth imaging. Airmass climbs steeply below about 25°.",
    "category": "Astronomy & Space",
    "file": "airmass-extinction-calculator.html",
    "path": "cards/airmass-extinction-calculator.html"
  },
  {
    "id": "algebra-title",
    "name": "algebra",
    "title": "Algebra Solver",
    "description": "Solve equations instantly. Type any equation and click Solve.",
    "category": "Mathematics",
    "file": "algebra.html",
    "path": "cards/algebra.html"
  },
  {
    "id": "anagram-solver-title",
    "name": "anagram-solver",
    "title": "🔤 Anagram Solver",
    "description": "Find every word you can make from your letters — from two letters up to the full anagram — with optional pattern matching.",
    "category": "Writing & Language",
    "file": "anagram-solver.html",
    "path": "cards/anagram-solver.html"
  },
  {
    "id": "anatomy-title",
    "name": "anatomy",
    "title": "Anatomy Tools & Facts",
    "description": "Body Mass Index",
    "category": "Science & Engineering",
    "file": "anatomy.html",
    "path": "cards/anatomy.html"
  },
  {
    "id": "ancient-egypt-quiz-title",
    "name": "ancient-egypt-quiz",
    "title": "🐫 Ancient Egypt Quiz",
    "description": "Test your knowledge of ancient Egypt — pharaohs, pyramids, gods and everyday life — in ten-question rounds with streaks.",
    "category": "Museum & Collection",
    "file": "ancient-egypt-quiz.html",
    "path": "cards/ancient-egypt-quiz.html"
  },
  {
    "id": "anime-binge-watch-calculator-title",
    "name": "anime-binge-watch-calculator",
    "title": "⏱️ Anime Binge Calculator",
    "description": "Calculate the exact time required to binge any anime series. Account for OP/ED skipping, filler elimination, playback speeds ($1.0\\times - 2.0\\times$), and view your estimated completion date.",
    "category": "Anime & Otaku Culture",
    "file": "anime-binge-watch-calculator.html",
    "path": "cards/anime-binge-watch-calculator.html"
  },
  {
    "id": "anime-character-archetype-matrix-title",
    "name": "anime-character-archetype-matrix",
    "title": "👑 Anime Character Archetypes",
    "description": "Explore the psychological Dere spectrum of anime character archetypes. Inspect behavioral triggers, iconic representatives, and take the 4-question archetype diagnostic quiz.",
    "category": "Anime & Otaku Culture",
    "file": "anime-character-archetype-matrix.html",
    "path": "cards/anime-character-archetype-matrix.html"
  },
  {
    "id": "anime-convention-budget-planner-title",
    "name": "anime-convention-budget-planner",
    "title": "🎪 Anime Con Budget Planner",
    "description": "Plan your anime convention expedition (Anime Expo, Otakon, Anime NYC, MCM). Split hotel costs across roommates, budget Artist Alley prints and scale figures, and enforce the golden 5-2-1 survival r...",
    "category": "Anime & Otaku Culture",
    "file": "anime-convention-budget-planner.html",
    "path": "cards/anime-convention-budget-planner.html"
  },
  {
    "id": "anime-cosplay-prop-scaler-title",
    "name": "anime-cosplay-prop-scaler",
    "title": "🗡️ Cosplay Prop Scaler",
    "description": "Scale anime weapons and props proportionally to your exact real-world body height. Calculate blade length, hilt dimensions, EVA foam sheet requirements, and convention-legal weight estimates.",
    "category": "Anime & Otaku Culture",
    "file": "anime-cosplay-prop-scaler.html",
    "path": "cards/anime-cosplay-prop-scaler.html"
  },
  {
    "id": "anime-filler-canon-guide-title",
    "name": "anime-filler-canon-guide",
    "title": "📜 Anime Filler Guide",
    "description": "Distinguish manga canon, anime canon, and skippable studio filler arcs across major long-running anime. Search any episode number or generate a streamlined, filler-free binge list.",
    "category": "Anime & Otaku Culture",
    "file": "anime-filler-canon-guide.html",
    "path": "cards/anime-filler-canon-guide.html"
  },
  {
    "id": "anime-japanese-phrases-tropes-title",
    "name": "anime-japanese-phrases-tropes",
    "title": "🎌 Anime Phrases & Tropes",
    "description": "Decode iconic anime verbal tics (*dattebayo*, *de gozaru*, *nya*), battle cries (*omae wa mou shindeiru*), and dialogue tropes with native Japanese audio pronunciation.",
    "category": "Anime & Otaku Culture",
    "file": "anime-japanese-phrases-tropes.html",
    "path": "cards/anime-japanese-phrases-tropes.html"
  },
  {
    "id": "anime-oped-music-analyzer-title",
    "name": "anime-oped-music-analyzer",
    "title": "🎵 Anime Music BPM Analyzer",
    "description": "Analyze the rhythmic energy of iconic Anime Openings and Endings. Explore the legendary Japanese TV 89-second broadcast rule, tap along with the real-time BPM tapper, and audition metronome tempos.",
    "category": "Anime & Otaku Culture",
    "file": "anime-oped-music-analyzer.html",
    "path": "cards/anime-oped-music-analyzer.html"
  },
  {
    "id": "anime-recommendation-mood-engine-title",
    "name": "anime-recommendation-mood-engine",
    "title": "🔮 Anime Mood Matcher",
    "description": "Find the perfect anime tailored to your exact emotional state and available time. Filter by desired mood (cathartic tears, adrenaline hype, psychological mind-games, or cozy healing), episode lengt...",
    "category": "Anime & Otaku Culture",
    "file": "anime-recommendation-mood-engine.html",
    "path": "cards/anime-recommendation-mood-engine.html"
  },
  {
    "id": "anime-release-schedule-converter-title",
    "name": "anime-release-schedule-converter",
    "title": "🕒 Anime Schedule Converter",
    "description": "Convert Tokyo Japan Standard Time (JST / UTC+9) anime broadcasts to your local timezone. Decodes Japanese TV late-night 30-hour clock conventions (e.g. 25:30 JST = 1:30 AM next day) and calculates ...",
    "category": "Anime & Otaku Culture",
    "file": "anime-release-schedule-converter.html",
    "path": "cards/anime-release-schedule-converter.html"
  },
  {
    "id": "antipode-gravity-tunnel-explorer-title",
    "name": "antipode-gravity-tunnel-explorer",
    "title": "🕳️ Antipode & Gravity Tunnel Explorer",
    "description": "Find the exact point on the far side of the planet from anywhere, then drill a straight frictionless tunnel to any second place and drop a capsule down it. The fall time is integrated through the r...",
    "category": "Science & Engineering",
    "file": "antipode-gravity-tunnel-explorer.html",
    "path": "cards/antipode-gravity-tunnel-explorer.html"
  },
  {
    "id": "apology-builder-title",
    "name": "apology-builder",
    "title": "🤝 Sincere Apology Builder",
    "description": "Most apologies fail for one of four reasons: they contain “but”, they apologise for the other person’s feelings instead of your behaviour, they explain rather than own it, or they...",
    "category": "Wellbeing & Community",
    "file": "apology-builder.html",
    "path": "cards/apology-builder.html"
  },
  {
    "id": "apr-apy-converter-title",
    "name": "apr-apy-converter",
    "title": "🏦 APR ⇄ APY Converter",
    "description": "APY = (1 + APR/n)n − 1, where n is compounds per year. APR is the quoted nominal rate; APY (EAR in the UK) is what you actually earn or pay after compounding. Savings ads in Britain must show AER.",
    "category": "Finance & Money",
    "file": "apr-apy-converter.html",
    "path": "cards/apr-apy-converter.html"
  },
  {
    "id": "aquarium-co2-drop-checker-calculator-title",
    "name": "aquarium-co2-drop-checker-calculator",
    "title": "🫧 Aquarium CO₂ Calculator",
    "description": "Dial in high-tech planted tank CO₂ injection. Calculate dissolved CO₂ concentration (ppm) from pH/KH equilibrium, simulate 4 dKH drop checker reagent colors, and estimate cylinder gas lifespan.",
    "category": "Aquatics & Fishkeeping",
    "file": "aquarium-co2-drop-checker-calculator.html",
    "path": "cards/aquarium-co2-drop-checker-calculator.html"
  },
  {
    "id": "aquarium-feeding-vacation-planner-title",
    "name": "aquarium-feeding-vacation-planner",
    "title": "🍤 Fish Feeding & Vacation Planner",
    "description": "Generate weekly nutrition schedules with gut-clearing fast days. Calculate safe vacation fasting limits, prevent the catastrophic \"neighbor overfeeding\" disaster, and generate foolproof pet-sitter ...",
    "category": "Aquatics & Fishkeeping",
    "file": "aquarium-feeding-vacation-planner.html",
    "path": "cards/aquarium-feeding-vacation-planner.html"
  },
  {
    "id": "aquarium-heater-chiller-calculator-title",
    "name": "aquarium-heater-chiller-calculator",
    "title": "🌡️ Aquarium Heater & Chiller",
    "description": "Calculate precision heating wattage, evaporative surface loss, and cooling chiller ratings. Eliminates the catastrophic \"stuck heater\" disaster using fail-safe dual heater redundancy math.",
    "category": "Aquatics & Fishkeeping",
    "file": "aquarium-heater-chiller-calculator.html",
    "path": "cards/aquarium-heater-chiller-calculator.html"
  },
  {
    "id": "aquarium-lighting-par-calculator-title",
    "name": "aquarium-lighting-par-calculator",
    "title": "💡 Aquarium PAR Lighting",
    "description": "Calculate photosynthetically active radiation (PAR) penetration at substrate depth, daily light integral (DLI), and generate split photoperiod schedules to suppress nuisance algae.",
    "category": "Aquatics & Fishkeeping",
    "file": "aquarium-lighting-par-calculator.html",
    "path": "cards/aquarium-lighting-par-calculator.html"
  },
  {
    "id": "aquarium-medication-dosing-calculator-title",
    "name": "aquarium-medication-dosing-calculator",
    "title": "💊 Fish Medication Dosing",
    "description": "Identify fish ailments by symptom and calculate precision medication dosages based on true net water volume. Includes invertebrate toxicity warnings and scaleless fish safety flags.",
    "category": "Aquatics & Fishkeeping",
    "file": "aquarium-medication-dosing-calculator.html",
    "path": "cards/aquarium-medication-dosing-calculator.html"
  },
  {
    "id": "aquarium-nitrogen-cycle-tracker-title",
    "name": "aquarium-nitrogen-cycle-tracker",
    "title": "🔄 Nitrogen Cycle Tracker",
    "description": "Master the nitrogen cycle without harming livestock. Calculate exact pure ammonia dosing, simulate bacterial colonisation curves (Nitrosomonas & Nitrospira), and validate your 24-hour clearance test.",
    "category": "Aquatics & Fishkeeping",
    "file": "aquarium-nitrogen-cycle-tracker.html",
    "path": "cards/aquarium-nitrogen-cycle-tracker.html"
  },
  {
    "id": "aquarium-stocking-compatibility-calculator-title",
    "name": "aquarium-stocking-compatibility-calculator",
    "title": "🐠 Fish Stocking Compatibility",
    "description": "Build your community aquarium roster. Calculates true metabolic bioload, swimming strata distribution (top, mid, bottom), temperature and pH overlap, and flags aggression and schooling warnings.",
    "category": "Aquatics & Fishkeeping",
    "file": "aquarium-stocking-compatibility-calculator.html",
    "path": "cards/aquarium-stocking-compatibility-calculator.html"
  },
  {
    "id": "aquarium-substrate-hardscape-calculator-title",
    "name": "aquarium-substrate-hardscape-calculator",
    "title": "🪨 Aquarium Substrate Estimator",
    "description": "Plan your planted tank and hardscape layout. Calculate exact substrate volume, sloped perspective depth, commercial bag counts (3L/9L aqua soil, 20lb/50lb sand), and stone weight for Iwagumi and Ry...",
    "category": "Aquatics & Fishkeeping",
    "file": "aquarium-substrate-hardscape-calculator.html",
    "path": "cards/aquarium-substrate-hardscape-calculator.html"
  },
  {
    "id": "aquarium-volume-weight-calculator-title",
    "name": "aquarium-volume-weight-calculator",
    "title": "🌊 Aquarium Volume & Weight",
    "description": "Calculate gross and true net water volume, accounting for glass thickness, top water margin, substrate, and hardscape displacement. Computes total filled weight and structural floor joist loading.",
    "category": "Aquatics & Fishkeeping",
    "file": "aquarium-volume-weight-calculator.html",
    "path": "cards/aquarium-volume-weight-calculator.html"
  },
  {
    "id": "aquarium-water-change-salinity-calculator-title",
    "name": "aquarium-water-change-salinity-calculator",
    "title": "🧪 Water Change & Salinity",
    "description": "Precision aquatic water chemistry toolkit. Calculate exact nitrate dilution percentages, RO/DI remineralization buffers for dwarf shrimp and plants, and marine saltwater salt batch mixing.",
    "category": "Aquatics & Fishkeeping",
    "file": "aquarium-water-change-salinity-calculator.html",
    "path": "cards/aquarium-water-change-salinity-calculator.html"
  },
  {
    "id": "archery-score-calculator-title",
    "name": "archery-score-calculator",
    "title": "🎯 Archery Score Calculator",
    "description": "Tap the value of each arrow as you shoot and this keeps the running total, your Xs and 10s, and how far through the round you are — the way scorers count at the line.",
    "category": "Sports",
    "file": "archery-score-calculator.html",
    "path": "cards/archery-score-calculator.html"
  },
  {
    "id": "architectural-orders-column-title",
    "name": "architectural-orders-column",
    "title": "🏛️ The Orders Bench",
    "description": "Vitruvius counted in modules: the lower diameter of the column. Doric is stocky, Corinthian tall and leafy, Ionic the volute in between. Enter a diameter in metres; the plaque returns shaft, capita...",
    "category": "Museum & Collection",
    "file": "architectural-orders-column.html",
    "path": "cards/architectural-orders-column.html"
  },
  {
    "id": "ascii-hex-binary-text-converter-title",
    "name": "ascii-hex-binary-text-converter",
    "title": "🔤 Text ⇄ Hex ⇄ Binary",
    "description": "Encode UTF-8 text as hex or binary, or decode hex/binary back. Spaces in hex are ignored. Binary is 8-bit groups. Nothing is sent anywhere.",
    "category": "Algorithms & Computer Science",
    "file": "ascii-hex-binary-text-converter.html",
    "path": "cards/ascii-hex-binary-text-converter.html"
  },
  {
    "id": "ascii-text-banner-art-generator-title",
    "name": "ascii-text-banner-art-generator",
    "title": "🔤 ASCII Banner Generator",
    "description": "Generate retro ASCII text banners and terminal art for code headers, GitHub READMEs, Discord bots, and CLI scripts.",
    "category": "Productivity & Lifestyle",
    "file": "ascii-text-banner-art-generator.html",
    "path": "cards/ascii-text-banner-art-generator.html"
  },
  {
    "id": "aspect-ratio-resizer-title",
    "name": "aspect-ratio-resizer",
    "title": "📐 Aspect Ratio Resizer",
    "description": "Calculate pixel dimensions while locking exact aspect ratios (16:9 widescreen, 9:16 vertical TikTok/Shorts, 4:3 classic, 1:1 square, 21:9 cinema). Generates modern CSS `aspect-ratio` code snippets.",
    "category": "Science & Engineering",
    "file": "aspect-ratio-resizer.html",
    "path": "cards/aspect-ratio-resizer.html"
  },
  {
    "id": "astronomy-title",
    "name": "astronomy",
    "title": "Astronomy Calculators",
    "description": "Planets move in elliptical orbits with the Sun at one focus.",
    "category": "Science & Engineering",
    "file": "astronomy.html",
    "path": "cards/astronomy.html"
  },
  {
    "id": "athletics-decathlon-points-calculator-title",
    "name": "athletics-decathlon-points-calculator",
    "title": "🥇 Athletics Decathlon & Heptathlon Points",
    "description": "The official World Athletics scoring tables: type a performance in any event and get its points, then watch the total build toward a world-class score. Times in seconds (or m:ss), jumps in centimet...",
    "category": "Sports",
    "file": "athletics-decathlon-points-calculator.html",
    "path": "cards/athletics-decathlon-points-calculator.html"
  },
  {
    "id": "atmospheric-aurora-borealis-field-title",
    "name": "atmospheric-aurora-borealis-field",
    "title": "🌌 Aurora Solar Wind Chamber",
    "description": "Kristian Birkeland's Terrella experiment. Solar wind plasma streams channeled along geomagnetic dipole field lines excite shimmering atmospheric auroral ovals.",
    "category": "Science & Engineering",
    "file": "atmospheric-aurora-borealis-field.html",
    "path": "cards/atmospheric-aurora-borealis-field.html"
  },
  {
    "id": "atmospheric-plasma-globe-title",
    "name": "atmospheric-plasma-globe",
    "title": "⚡ Tesla Atmospheric Plasma",
    "description": "High-frequency Tesla coil discharge globe. Noble gas ionization streamers branch from the central electrode and focus to your touch via capacitive coupling.",
    "category": "Science & Engineering",
    "file": "atmospheric-plasma-globe.html",
    "path": "cards/atmospheric-plasma-globe.html"
  },
  {
    "id": "audio-bpm-tapper-title",
    "name": "audio-bpm-tapper",
    "title": "🥁 Beat BPM Tapper",
    "description": "Tap to the rhythm of any track or beat. Calculates exact BPM, musical delay times in milliseconds, reverb pre-delay values, and audio frequency modulation timings for music producers and DJs.",
    "category": "Music & Audio",
    "file": "audio-bpm-tapper.html",
    "path": "cards/audio-bpm-tapper.html"
  },
  {
    "id": "audio-file-size-calculator-title",
    "name": "audio-file-size-calculator",
    "title": "🎧 Audio File Size",
    "description": "Uncompressed WAV/AIFF size = sample rate × channels × (bit depth ÷ 8) × seconds. MP3/AAC size ≈ bitrate × seconds ÷ 8. Headers are a few kilobytes — ignored here.",
    "category": "Algorithms & Computer Science",
    "file": "audio-file-size-calculator.html",
    "path": "cards/audio-file-size-calculator.html"
  },
  {
    "id": "audio-tone-frequency-generator-title",
    "name": "audio-tone-frequency-generator",
    "title": "🎚️ Audio Tone Generator",
    "description": "Generate pure acoustic tones, test speaker frequency responses, and monitor live audio waveforms using the Web Audio API.",
    "category": "Music & Audio",
    "file": "audio-tone-frequency-generator.html",
    "path": "cards/audio-tone-frequency-generator.html"
  },
  {
    "id": "awkward-silence-filler-title",
    "name": "awkward-silence-filler",
    "title": "🗣️ Awkward Silence Filler",
    "description": "The silence is deafening. Someone needs to say something. Let us help. (Results may make it worse.)",
    "category": "Productivity & Lifestyle",
    "file": "awkward-silence-filler.html",
    "path": "cards/awkward-silence-filler.html"
  },
  {
    "id": "b2b-cold-email-sequence-generator-title",
    "name": "b2b-cold-email-sequence-generator",
    "title": "✉️ B2B Cold Email Generator",
    "description": "Generate high-converting 4-touch B2B cold email sequences. Features real-time spam keyword detection and an inbox deliverability health score. Replaces expensive monthly sales automation subscripti...",
    "category": "SaaS & Business Killers",
    "file": "b2b-cold-email-sequence-generator.html",
    "path": "cards/b2b-cold-email-sequence-generator.html"
  },
  {
    "id": "baby-formula-mixing-calculator-title",
    "name": "baby-formula-mixing-calculator",
    "title": "🍼 Baby Formula Mixing",
    "description": "Most UK powders use 1 level scoop per 30 ml of water (check the tin). Water first, then powder. This is arithmetic — NHS mixing and sterilising steps still apply, and never microwave a bottle.",
    "category": "Health & Fitness",
    "file": "baby-formula-mixing-calculator.html",
    "path": "cards/baby-formula-mixing-calculator.html"
  },
  {
    "id": "baby-sleep-planner-title",
    "name": "baby-sleep-planner",
    "title": "🍼 Baby Sleep & Feeding Day Planner",
    "description": "Babies run on wake windows — how long they can stay awake before they need to sleep again. It changes fast in the first year and getting it wrong by half an hour is usually the difference between a...",
    "category": "Health & Fitness",
    "file": "baby-sleep-planner.html",
    "path": "cards/baby-sleep-planner.html"
  },
  {
    "id": "backyard-bird-feeder-diet-title",
    "name": "backyard-bird-feeder-diet",
    "title": "🌻 Backyard Bird Feeder Nutrition",
    "description": "Avian nutritional formulation matrix. Matches seed types to bill morphology, prevents feeder pests (squirrels/starlings), and maintains disease-free feeding stations.",
    "category": "Birdwatching & Ornithology",
    "file": "backyard-bird-feeder-diet.html",
    "path": "cards/backyard-bird-feeder-diet.html"
  },
  {
    "id": "badminton-scorekeeper-title",
    "name": "badminton-scorekeeper",
    "title": "🏸 Badminton Match Scorer",
    "description": "Rally scoring to 21, win by two — but a game can only go to 30. Tap a side to add their point and this handles the deuce, the game win, and the best-of-three match for you.",
    "category": "Sports",
    "file": "badminton-scorekeeper.html",
    "path": "cards/badminton-scorekeeper.html"
  },
  {
    "id": "bank-complaint-tracker-title",
    "name": "bank-complaint-tracker",
    "title": "📅 Bank Complaint Deadline Tracker",
    "description": "Track your complaint deadlines — never miss a bank's response window, FOS deadline, or court limitation period",
    "category": "Finance & Money",
    "file": "bank-complaint-tracker.html",
    "path": "cards/bank-complaint-tracker.html"
  },
  {
    "id": "bank-credit-score-dispute-title",
    "name": "bank-credit-score-dispute",
    "title": "📊 Credit Score Dispute Letter Generator",
    "description": "Challenge incorrect entries on your credit report — generate dispute letters for credit agencies and banks",
    "category": "Finance & Money",
    "file": "bank-credit-score-dispute.html",
    "path": "cards/bank-credit-score-dispute.html"
  },
  {
    "id": "bank-dispute-letter-title",
    "name": "bank-dispute-letter",
    "title": "✉️ Bank Charge Dispute Letter Generator",
    "description": "Generate formal dispute letters for unauthorized charges, unfair fees, and billing errors — ready to send to your bank",
    "category": "Finance & Money",
    "file": "bank-dispute-letter.html",
    "path": "cards/bank-dispute-letter.html"
  },
  {
    "id": "bank-fee-calculator-title",
    "name": "bank-fee-calculator",
    "title": "💰 Hidden Bank Fee Calculator",
    "description": "Calculate the TRUE cost of your bank account — overdraft fees, ATM charges, FX markups, and hidden costs that banks hope you won't notice",
    "category": "Finance & Money",
    "file": "bank-fee-calculator.html",
    "path": "cards/bank-fee-calculator.html"
  },
  {
    "id": "bank-fos-complaint-title",
    "name": "bank-fos-complaint",
    "title": "⚖️ Financial Ombudsman Complaint Builder",
    "description": "Build a complete FOS complaint — step by step. Get your money back when the bank refuses to help",
    "category": "Finance & Money",
    "file": "bank-fos-complaint.html",
    "path": "cards/bank-fos-complaint.html"
  },
  {
    "id": "bank-interest-reclaim-title",
    "name": "bank-interest-reclaim",
    "title": "📊 Overdraft & Interest Reclaim Calculator",
    "description": "Calculate how much you've been overcharged on overdraft interest and fees — then generate a reclaim letter",
    "category": "Finance & Money",
    "file": "bank-interest-reclaim.html",
    "path": "cards/bank-interest-reclaim.html"
  },
  {
    "id": "bank-sar-request-title",
    "name": "bank-sar-request",
    "title": "🔍 Subject Access Request (SAR) Generator",
    "description": "Force your bank to reveal ALL data they hold on you — internal notes, decision records, credit scoring, and communications",
    "category": "Finance & Money",
    "file": "bank-sar-request.html",
    "path": "cards/bank-sar-request.html"
  },
  {
    "id": "bank-section75-claim-title",
    "name": "bank-section75-claim",
    "title": "🛡️ Section 75 Claim Calculator & Letter",
    "description": "Check if your credit card purchase is protected under Section 75 — calculate your claim and generate the letter",
    "category": "Finance & Money",
    "file": "bank-section75-claim.html",
    "path": "cards/bank-section75-claim.html"
  },
  {
    "id": "bank-small-claims-title",
    "name": "bank-small-claims",
    "title": "⚖️ Small Claims Court Guide & Cost Calculator",
    "description": "Calculate court costs, check eligibility, and generate your claim — the nuclear option when banks refuse to play fair",
    "category": "Finance & Money",
    "file": "bank-small-claims.html",
    "path": "cards/bank-small-claims.html"
  },
  {
    "id": "bank-switching-calculator-title",
    "name": "bank-switching-calculator",
    "title": "🔄 Bank Switching Bonus Calculator",
    "description": "Compare bank switching bonuses, calculate total savings, and see how much your loyalty is costing you",
    "category": "Finance & Money",
    "file": "bank-switching-calculator.html",
    "path": "cards/bank-switching-calculator.html"
  },
  {
    "id": "bar-psi-kpa-pressure-converter-title",
    "name": "bar-psi-kpa-pressure-converter",
    "title": "⏲️ Bar ⇄ PSI ⇄ kPa",
    "description": "Tyre, compressor and scuba pressures. 1 bar = 100 kPa = 14.5038 psi. Standard atmosphere is 101.325 kPa (14.696 psi). Gauge vs absolute is your problem — this is a unit convert only.",
    "category": "Science & Engineering",
    "file": "bar-psi-kpa-pressure-converter.html",
    "path": "cards/bar-psi-kpa-pressure-converter.html"
  },
  {
    "id": "barnsley-fern-fractal-title",
    "name": "barnsley-fern-fractal",
    "title": "🌿 Barnsley Fern",
    "description": "Four simple rules, chosen at random, draw a perfect fern. No one programmed a leaf — the fern is the fixed point of the chaos, and every frond is a tiny copy of the whole.",
    "category": "Mind-Blowing Demos",
    "file": "barnsley-fern-fractal.html",
    "path": "cards/barnsley-fern-fractal.html"
  },
  {
    "id": "base64-file-text-encoder-decoder-title",
    "name": "base64-file-text-encoder-decoder",
    "title": "🔤 Base64 Text & File Encoder / Decoder",
    "description": "Encode and decode UTF-8 text, emojis, source code, and files to Base64 and Data URLs with byte statistics, live image preview, and URL-safe formats.",
    "category": "Algorithms & Computer Science",
    "file": "base64-file-text-encoder-decoder.html",
    "path": "cards/base64-file-text-encoder-decoder.html"
  },
  {
    "id": "base64-text-encoder-decoder-title",
    "name": "base64-text-encoder-decoder",
    "title": "🔐 Base64, Hex & Binary Text Encoder / Decoder",
    "description": "Encode text to Base64 (standard or URL-safe), hexadecimal, binary, HTML entities, Unicode escapes or ROT13 — and decode back. Full UTF-8 and emoji support. Live in both directions; nothing leaves y...",
    "category": "Algorithms & Computer Science",
    "file": "base64-text-encoder-decoder.html",
    "path": "cards/base64-text-encoder-decoder.html"
  },
  {
    "id": "baseball-stats-calculator-title",
    "name": "baseball-stats-calculator",
    "title": "⚾ Baseball Stats Calculator",
    "description": "The slash line every hitter lives by — batting average, on-base and slugging, plus OPS — and the pitching numbers (ERA and WHIP). Enter a box score and get the exact formulas and a read on what the...",
    "category": "Sports",
    "file": "baseball-stats-calculator.html",
    "path": "cards/baseball-stats-calculator.html"
  },
  {
    "id": "basketball-efficiency-calculator-title",
    "name": "basketball-efficiency-calculator",
    "title": "🏀 Basketball Efficiency Calculator",
    "description": "Type in a box score and get the metrics the analysts use: Game Score, effective and true shooting percentage, points per shot and assist-to-turnover ratio — all with the exact formulas and a plain-...",
    "category": "Sports",
    "file": "basketball-efficiency-calculator.html",
    "path": "cards/basketball-efficiency-calculator.html"
  },
  {
    "id": "battery-runtime-mah-calculator-title",
    "name": "battery-runtime-mah-calculator",
    "title": "🔋 Battery Runtime (mAh)",
    "description": "Hours ≈ (capacity mAh × (voltage / load voltage) × efficiency) / load mA. A 2000 mAh cell at 100 mA is about 20 hours at 100% — real packs are less because of cut-off voltage and converter loss.",
    "category": "Science & Engineering",
    "file": "battery-runtime-mah-calculator.html",
    "path": "cards/battery-runtime-mah-calculator.html"
  },
  {
    "id": "battery-sizing-title",
    "name": "battery-sizing",
    "title": "Battery Sizing Calculator",
    "description": "Accounts for battery aging, temperature, and discharge limits",
    "category": "Science & Engineering",
    "file": "battery-sizing.html",
    "path": "cards/battery-sizing.html"
  },
  {
    "id": "bayes-chance-hall-title",
    "name": "bayes-chance-hall",
    "title": "🧠 The Bayes Workshop",
    "description": "Conditional probability you can feel: what a positive test really means (Bayes' theorem), a 300-game Monty Hall simulation, and the prosecutor's fallacy — with a 10,000-person grid painted live by ...",
    "category": "Museum & Collection",
    "file": "bayes-chance-hall.html",
    "path": "cards/bayes-chance-hall.html"
  },
  {
    "id": "beam-vibration-modal-analysis-title",
    "name": "beam-vibration-modal-analysis",
    "title": "🏗️ Beam Vibration Analyzer",
    "description": "Compute natural flexural vibration eigenfrequencies and mode shapes for structural beams ($EI \\frac{\\partial^4 w}{\\partial x^4} + \\rho A \\frac{\\partial^2 w}{\\partial t^2} = 0$). Inspect nodal point...",
    "category": "Science & Engineering",
    "file": "beam-vibration-modal-analysis.html",
    "path": "cards/beam-vibration-modal-analysis.html"
  },
  {
    "id": "beaufort-wind-scale-title",
    "name": "beaufort-wind-scale",
    "title": "🌬️ Beaufort Wind Scale",
    "description": "Convert wind speed to a Beaufort force (0–12) using the Met Office mean-speed bands. Force is a class, not a precision instrument. Gusts can sit a force higher than the mean.",
    "category": "Science & Engineering",
    "file": "beaufort-wind-scale.html",
    "path": "cards/beaufort-wind-scale.html"
  },
  {
    "id": "bernoulli-levitating-air-stream-title",
    "name": "bernoulli-levitating-air-stream",
    "title": "🎈 Coanda & Bernoulli Air Levitation",
    "description": "Aerodynamic levitation exhibit. High-velocity air jet traps a floating sphere via Bernoulli low-pressure depression and Coandă wall adhesion even when tilted.",
    "category": "Science & Engineering",
    "file": "bernoulli-levitating-air-stream.html",
    "path": "cards/bernoulli-levitating-air-stream.html"
  },
  {
    "id": "betting-odds-each-way-calculator-title",
    "name": "betting-odds-each-way-calculator",
    "title": "🎰 Betting Odds & Each-Way Calculator",
    "description": "Work out fractional odds as a decimal and a probability, and see exactly what an each-way bet returns — whether your horse wins, only places, or finishes nowhere. The stake, odds and place terms al...",
    "category": "Sports",
    "file": "betting-odds-each-way-calculator.html",
    "path": "cards/betting-odds-each-way-calculator.html"
  },
  {
    "id": "bifurcation-diagram-logistic-map-title",
    "name": "bifurcation-diagram-logistic-map",
    "title": "🦋 Bifurcation: Order to Chaos",
    "description": "One equation, one knob. The logistic map x → r·x·(1−x) doubles its rhythm again and again, then dissolves into chaos — and the same pattern of period-doubling appears acros...",
    "category": "Mind-Blowing Demos",
    "file": "bifurcation-diagram-logistic-map.html",
    "path": "cards/bifurcation-diagram-logistic-map.html"
  },
  {
    "id": "big-o-complexity-explorer-title",
    "name": "big-o-complexity-explorer",
    "title": "📈 Big-O Complexity Explorer",
    "description": "Why does an O(n²) algorithm feel instant for 10 items but crawl for a million? Watch each complexity class grow, and see how long each would really take at one operation per nanosecond — the n...",
    "category": "Algorithms & Computer Science",
    "file": "big-o-complexity-explorer.html",
    "path": "cards/big-o-complexity-explorer.html"
  },
  {
    "id": "bike-gear-calculator-title",
    "name": "bike-gear-calculator",
    "title": "🚴 Bike Gear, Cadence & Speed Calculator",
    "description": "Works out what every gear on your bike actually does — how far one pedal turn takes you, what speed you will be doing at a given cadence, and which gears are duplicates you never need. The thing mo...",
    "category": "Sports",
    "file": "bike-gear-calculator.html",
    "path": "cards/bike-gear-calculator.html"
  },
  {
    "id": "binary-bits-bitwise-playground-title",
    "name": "binary-bits-bitwise-playground",
    "title": "🔢 Binary, Bits & Bitwise Playground",
    "description": "Everything on a computer is bits. Tap the cells to flip bits and see the number change, then run the bitwise operations — AND, OR, XOR, NOT, shifts — that power everything from colours to cryptogra...",
    "category": "Algorithms & Computer Science",
    "file": "binary-bits-bitwise-playground.html",
    "path": "cards/binary-bits-bitwise-playground.html"
  },
  {
    "id": "binaural-lucid-frequency-gen-title",
    "name": "binaural-lucid-frequency-gen",
    "title": "🎧 Lucid Binaural REM Stimulator",
    "description": "Real-time stereo binaural synthesizer with 40 Hz gamma stimulation (Voss et al., Nature Neuroscience 2014) and 6 Hz theta hypnagogic carriers. Requires stereo headphones.",
    "category": "Lucid Dreaming & Sleep",
    "file": "binaural-lucid-frequency-gen.html",
    "path": "cards/binaural-lucid-frequency-gen.html"
  },
  {
    "id": "binaural-neuro-tuner-title",
    "name": "binaural-neuro-tuner",
    "title": "🧠 Binaural Neuro Tuner",
    "description": "Generate scientifically tuned binaural beats and isochronic frequencies using pure Web Audio synthesis. Entrain your brainwaves for laser focus, flow state, deep meditation, or rapid sleep. 🎧 Head...",
    "category": "Music & Audio",
    "file": "binaural-neuro-tuner.html",
    "path": "cards/binaural-neuro-tuner.html"
  },
  {
    "id": "biology-tools-title",
    "name": "biology-tools",
    "title": "Biology Tools",
    "description": "Quick Guide",
    "category": "Science & Engineering",
    "file": "biology-tools.html",
    "path": "cards/biology-tools.html"
  },
  {
    "id": "bioma-evolutionary-petri-dish-title",
    "name": "bioma-evolutionary-petri-dish",
    "title": "🦠 Bioma Petri Dish",
    "description": "An artificial life (ALife) Darwinian simulation. Engineer genetic cellular strains, watch natural selection optimize camouflage and hunting behaviors across thousands of generations, and introduce ...",
    "category": "Interactive Art & Living Worlds",
    "file": "bioma-evolutionary-petri-dish.html",
    "path": "cards/bioma-evolutionary-petri-dish.html"
  },
  {
    "id": "bird-migration-weather-calc-title",
    "name": "bird-migration-weather-calc",
    "title": "🌤️ Migration & Thermal Lift Calc",
    "description": "Predict hawk watches, songbird flyways, and coastal fallouts. Evaluates synoptic frontal boundaries, barometric rise, wind vectors, and solar thermal lift.",
    "category": "Birdwatching & Ornithology",
    "file": "bird-migration-weather-calc.html",
    "path": "cards/bird-migration-weather-calc.html"
  },
  {
    "id": "bird-molt-cycle-ageing-title",
    "name": "bird-molt-cycle-ageing",
    "title": "🪶 Bird Molt Cycle & Ageing Lab",
    "description": "Avian Humphrey-Parkes (H-P) plumage terminology and molt-limit ageing engine. Decode annual feather replacement cycles between juvenile, alternate, and basic plumages.",
    "category": "Birdwatching & Ornithology",
    "file": "bird-molt-cycle-ageing.html",
    "path": "cards/bird-molt-cycle-ageing.html"
  },
  {
    "id": "bird-nest-box-hole-sizing-title",
    "name": "bird-nest-box-hole-sizing",
    "title": "🪺 Bird Nest Box Dimensions Guide",
    "description": "Cornell Lab of Ornithology nest box builder. Exact hole diameters, interior floor dimensions, and predator exclusion clearance for native cavity nesters.",
    "category": "Birdwatching & Ornithology",
    "file": "bird-nest-box-hole-sizing.html",
    "path": "cards/bird-nest-box-hole-sizing.html"
  },
  {
    "id": "bird-silhouette-flight-id-title",
    "name": "bird-silhouette-flight-id",
    "title": "🦅 Raptor & Flight Silhouette ID",
    "description": "Identify raptors and aerial birds in high-overhead flight by wing aspect ratio, tail proportions, wingtip finger slots, and characteristic wingbeat cadence.",
    "category": "Birdwatching & Ornithology",
    "file": "bird-silhouette-flight-id.html",
    "path": "cards/bird-silhouette-flight-id.html"
  },
  {
    "id": "bird-song-mnemonic-trainer-title",
    "name": "bird-song-mnemonic-trainer",
    "title": "🎶 Bird Song Mnemonic Trainer",
    "description": "Acoustic field ornithology trainer. Decode avian vocalizations using phonetic mnemonics, pitch contours, and synthesized frequency playback.",
    "category": "Birdwatching & Ornithology",
    "file": "bird-song-mnemonic-trainer.html",
    "path": "cards/bird-song-mnemonic-trainer.html"
  },
  {
    "id": "bird-topography-field-marks-title",
    "name": "bird-topography-field-marks",
    "title": "🔍 Avian Anatomy & Field Marks",
    "description": "Standard ornithological avian topography map. Learn precise feather tracts, facial stripes, wing coverts, and bill structures to nail difficult field identifications.",
    "category": "Birdwatching & Ornithology",
    "file": "bird-topography-field-marks.html",
    "path": "cards/bird-topography-field-marks.html"
  },
  {
    "id": "birding-binocular-optics-calc-title",
    "name": "birding-binocular-optics-calc",
    "title": "🔭 Binocular Optics & FOV Lab",
    "description": "Optical performance evaluator for birdwatchers. Calculates exit pupil, twilight factor, relative brightness, and converts field of view across feet, meters, and angular degrees.",
    "category": "Birdwatching & Ornithology",
    "file": "birding-binocular-optics-calc.html",
    "path": "cards/birding-binocular-optics-calc.html"
  },
  {
    "id": "birding-life-list-tally-title",
    "name": "birding-life-list-tally",
    "title": "📋 Birding Life List & Big Year",
    "description": "Personal field lifer ledger & annual Big Year tally. Records lifetime ticks, date of observation, habitat biome, and exports to CSV for eBird backup.",
    "category": "Birdwatching & Ornithology",
    "file": "birding-life-list-tally.html",
    "path": "cards/birding-life-list-tally.html"
  },
  {
    "id": "birthday-title",
    "name": "birthday",
    "title": "Birthday Reminder",
    "description": "No birthdays added yet. Add your first birthday above!",
    "category": "Productivity & Lifestyle",
    "file": "birthday.html",
    "path": "cards/birthday.html"
  },
  {
    "id": "black-hole-horizon-calculator-title",
    "name": "black-hole-horizon-calculator",
    "title": "🕳️ Black Hole Horizon Calculator",
    "description": "Event horizon radius, surface gravity, Hawking temperature, evaporation time and the tidal force at the horizon for any mass. Compares stellar and supermassive black holes side by side.",
    "category": "Astronomy & Space",
    "file": "black-hole-horizon-calculator.html",
    "path": "cards/black-hole-horizon-calculator.html"
  },
  {
    "id": "blame-deflector-title",
    "name": "blame-deflector",
    "title": "💢 Blame Deflector 3000",
    "description": "Something went wrong? Don't worry — it's definitely not your fault. Let science* find someone else to blame. *Not science.",
    "category": "Productivity & Lifestyle",
    "file": "blame-deflector.html",
    "path": "cards/blame-deflector.html"
  },
  {
    "id": "blood-pressure-category-guide-title",
    "name": "blood-pressure-category-guide",
    "title": "🩺 Blood Pressure Category Guide",
    "description": "Home-monitor numbers compared with NHS adult clinic bands (and a note on AHA). One reading is not a diagnosis. Seek urgent help for chest pain, one-sided weakness, or a sudden severe headache. This...",
    "category": "Health & Fitness",
    "file": "blood-pressure-category-guide.html",
    "path": "cards/blood-pressure-category-guide.html"
  },
  {
    "id": "bmi-title",
    "name": "bmi",
    "title": "⚕️ BMI Calculator",
    "description": "Calculate your Body Mass Index (BMI) with accurate WHO classification. BMI is a simple screening tool for weight categories that may lead to health problems.",
    "category": "Health & Fitness",
    "file": "bmi.html",
    "path": "cards/bmi.html"
  },
  {
    "id": "bmr-title",
    "name": "bmr",
    "title": "🔥 BMR & TDEE Calculator",
    "description": "Calculate your Basal Metabolic Rate (BMR) and Total Daily Energy Expenditure (TDEE) using scientifically validated formulas.",
    "category": "Health & Fitness",
    "file": "bmr.html",
    "path": "cards/bmr.html"
  },
  {
    "id": "board-foot-lumber-calculator-title",
    "name": "board-foot-lumber-calculator",
    "title": "🪵 Board-Foot Lumber Calculator",
    "description": "A board foot is 1\" × 12\" × 12\". Enter the dimensions of your boards and the quantity, and get the board footage, linear footage and cost.",
    "category": "Home & DIY",
    "file": "board-foot-lumber-calculator.html",
    "path": "cards/board-foot-lumber-calculator.html"
  },
  {
    "id": "boardgame-backgammon-title",
    "name": "boardgame-backgammon",
    "title": "🎲 Backgammon",
    "description": "Classic backgammon: move your pieces around the board and bear them off first. Roll dice and race against the AI!",
    "category": "MrProphecy Arcade",
    "file": "boardgame-backgammon.html",
    "path": "cards/boardgame-backgammon.html"
  },
  {
    "id": "boardgame-checkers-title",
    "name": "boardgame-checkers",
    "title": "🔴⚫ Checkers / Draughts",
    "description": "Classic checkers with mandatory jumps and king promotion. Click a piece then click where to move. Play against the AI.",
    "category": "MrProphecy Arcade",
    "file": "boardgame-checkers.html",
    "path": "cards/boardgame-checkers.html"
  },
  {
    "id": "boardgame-chess-title",
    "name": "boardgame-chess",
    "title": "♟️ Chess",
    "description": "Play chess against a simple AI. Full rules: castling, en passant, pawn promotion. Click a piece then click where to move.",
    "category": "MrProphecy Arcade",
    "file": "boardgame-chess.html",
    "path": "cards/boardgame-chess.html"
  },
  {
    "id": "boardgame-connect-four-title",
    "name": "boardgame-connect-four",
    "title": "🔴⚫ Connect Four",
    "description": "Drop discs to connect four in a row — horizontally, vertically, or diagonally. Play against a smart AI with animations.",
    "category": "MrProphecy Arcade",
    "file": "boardgame-connect-four.html",
    "path": "cards/boardgame-connect-four.html"
  },
  {
    "id": "boardgame-dominoes-title",
    "name": "boardgame-dominoes",
    "title": "🁣 Dominoes",
    "description": "Block dominoes: match ends to play your tiles. If you can't play, draw from the boneyard. Lowest hand score wins!",
    "category": "MrProphecy Arcade",
    "file": "boardgame-dominoes.html",
    "path": "cards/boardgame-dominoes.html"
  },
  {
    "id": "boardgame-ludo-title",
    "name": "boardgame-ludo",
    "title": "🎲 Ludo",
    "description": "Race your 4 tokens from start to home! Roll a 6 to enter the board. Land on opponents to send them back. 2-4 player local.",
    "category": "MrProphecy Arcade",
    "file": "boardgame-ludo.html",
    "path": "cards/boardgame-ludo.html"
  },
  {
    "id": "boardgame-mancala-title",
    "name": "boardgame-mancala",
    "title": "🪨 Mancala",
    "description": "Ancient strategy game — sow seeds around the board, capture your opponent's stones. Free turn if your last seed lands in your store.",
    "category": "MrProphecy Arcade",
    "file": "boardgame-mancala.html",
    "path": "cards/boardgame-mancala.html"
  },
  {
    "id": "boardgame-nine-mens-morris-title",
    "name": "boardgame-nine-mens-morris",
    "title": "⚬ Nine Men's Morris",
    "description": "Place and slide pieces to form mills (3 in a row). A mill lets you remove an opponent's piece. Reduce them to 2 to win!",
    "category": "MrProphecy Arcade",
    "file": "boardgame-nine-mens-morris.html",
    "path": "cards/boardgame-nine-mens-morris.html"
  },
  {
    "id": "boardgame-othello-title",
    "name": "boardgame-othello",
    "title": "⚫⚪ Othello (Reversi)",
    "description": "Place discs to flip your opponent's pieces. The player with the most discs when the board is full wins. Play against a strategic AI.",
    "category": "MrProphecy Arcade",
    "file": "boardgame-othello.html",
    "path": "cards/boardgame-othello.html"
  },
  {
    "id": "boardgame-snakes-ladders-title",
    "name": "boardgame-snakes-ladders",
    "title": "🐍 Snakes & Ladders",
    "description": "Roll the dice and race to square 100! Ladders boost you up, snakes drag you down. Play against the AI on a beautiful animated board.",
    "category": "MrProphecy Arcade",
    "file": "boardgame-snakes-ladders.html",
    "path": "cards/boardgame-snakes-ladders.html"
  },
  {
    "id": "boardgame-yahtzee-title",
    "name": "boardgame-yahtzee",
    "title": "🎲 Yahtzee",
    "description": "Roll five dice up to three times per turn. Score in 13 categories. Get the highest total!",
    "category": "MrProphecy Arcade",
    "file": "boardgame-yahtzee.html",
    "path": "cards/boardgame-yahtzee.html"
  },
  {
    "id": "body-surface-area-calculator-title",
    "name": "body-surface-area-calculator",
    "title": "🧍 Body Surface Area Calculator",
    "description": "Estimate body surface area with Mosteller, Du Bois and Haycock formulae from height and weight. Used for some drug doses and cardiac index. Educational only — never override a prescribed dose.",
    "category": "Health & Fitness",
    "file": "body-surface-area-calculator.html",
    "path": "cards/body-surface-area-calculator.html"
  },
  {
    "id": "bodyfat-title",
    "name": "bodyfat",
    "title": "🏋️ Body Fat Calculator",
    "description": "Estimate your body fat percentage using the U.S. Navy method and understand your fitness level.",
    "category": "Health & Fitness",
    "file": "bodyfat.html",
    "path": "cards/bodyfat.html"
  },
  {
    "id": "boiling-point-finder-title",
    "name": "boiling-point-finder",
    "title": "Boiling Point Finder",
    "description": "Quick Examples:",
    "category": "Science & Engineering",
    "file": "boiling-point-finder.html",
    "path": "cards/boiling-point-finder.html"
  },
  {
    "id": "bouldering-score-calculator-title",
    "name": "bouldering-score-calculator",
    "title": "🧗 Bouldering Score Comparison",
    "description": "In bouldering, tops beat everything. Enter two climbers' results and this applies the ranking order — most tops, then fewest attempts to top, then most zones, then fewest attempts to zone — and dec...",
    "category": "Sports",
    "file": "bouldering-score-calculator.html",
    "path": "cards/bouldering-score-calculator.html"
  },
  {
    "id": "bowling-score-calculator-title",
    "name": "bowling-score-calculator",
    "title": "🎳 Ten-Pin Bowling Score Calculator",
    "description": "Enter the pinfall for each roll and this scores the game for you — strikes and spares with the bonuses, and the tenth frame's extra balls, all handled automatically.",
    "category": "Sports",
    "file": "bowling-score-calculator.html",
    "path": "cards/bowling-score-calculator.html"
  },
  {
    "id": "boxing-fight-decision-predictor-title",
    "name": "boxing-fight-decision-predictor",
    "title": "📊 Boxing Fight Outcome Projector",
    "description": "Mid-fight maths for fans and cornermen. Enter the score so far and see exactly what each fighter needs in the remaining rounds — including whether a knockout has become the only route.",
    "category": "Sports",
    "file": "boxing-fight-decision-predictor.html",
    "path": "cards/boxing-fight-decision-predictor.html"
  },
  {
    "id": "boxing-judge-criteria-trainer-title",
    "name": "boxing-judge-criteria-trainer",
    "title": "⚖️ Boxing Judging Criteria Weigher",
    "description": "Score a single round against the four official criteria — clean punching, effective aggression, ring generalship and defence — in their correct priority order. Shows which criterion decided the round.",
    "category": "Sports",
    "file": "boxing-judge-criteria-trainer.html",
    "path": "cards/boxing-judge-criteria-trainer.html"
  },
  {
    "id": "boxing-knockdown-count-rules-title",
    "name": "boxing-knockdown-count-rules",
    "title": "🛎️ Boxing Knockdown & Count Rules Assistant",
    "description": "Work out whether an incident is a scoring knockdown or a slip, how the count runs, and what it does to the round score. Includes a live count timer at the official pace.",
    "category": "Sports",
    "file": "boxing-knockdown-count-rules.html",
    "path": "cards/boxing-knockdown-count-rules.html"
  },
  {
    "id": "boxing-punch-stat-tracker-title",
    "name": "boxing-punch-stat-tracker",
    "title": "👊 Boxing Punch Stat Tracker",
    "description": "Live compubox-style punch counter. Tap as you watch to log jabs and power shots landed or thrown, and get instant connect percentages plus a work-rate comparison.",
    "category": "Sports",
    "file": "boxing-punch-stat-tracker.html",
    "path": "cards/boxing-punch-stat-tracker.html"
  },
  {
    "id": "boxing-round-by-round-analyzer-title",
    "name": "boxing-round-by-round-analyzer",
    "title": "📈 Boxing Momentum & Swing Round Analyser",
    "description": "Paste a completed card and see the shape of the fight — momentum swings, the longest run of rounds, who finished stronger, and which rounds were decisive enough to change the result.",
    "category": "Sports",
    "file": "boxing-round-by-round-analyzer.html",
    "path": "cards/boxing-round-by-round-analyzer.html"
  },
  {
    "id": "boxing-round-timer-bell-title",
    "name": "boxing-round-timer-bell",
    "title": "🔔 Boxing Round Timer & Bell",
    "description": "Full bout timer with authentic bell and ten-second clapper, generated live in your browser. Configure round length, rest interval and round count for sparring, training or scoring practice.",
    "category": "Sports",
    "file": "boxing-round-timer-bell.html",
    "path": "cards/boxing-round-timer-bell.html"
  },
  {
    "id": "boxing-scorecard-comparator-title",
    "name": "boxing-scorecard-comparator",
    "title": "🔍 Boxing Scorecard Comparator",
    "description": "Compare your card against the official judges round by round. Highlights exactly where you disagreed, measures your agreement rate, and flags the swing rounds that decided the fight.",
    "category": "Sports",
    "file": "boxing-scorecard-comparator.html",
    "path": "cards/boxing-scorecard-comparator.html"
  },
  {
    "id": "boxing-ten-point-must-scorecard-title",
    "name": "boxing-ten-point-must-scorecard",
    "title": "🥊 Boxing 10-Point Must Scorecard",
    "description": "Score a fight round by round using the official 10-Point Must System. Knockdowns and point deductions are applied automatically, with a live running total and winner projection.",
    "category": "Sports",
    "file": "boxing-ten-point-must-scorecard.html",
    "path": "cards/boxing-ten-point-must-scorecard.html"
  },
  {
    "id": "boxing-three-judge-simulator-title",
    "name": "boxing-three-judge-simulator",
    "title": "👨‍⚖️ Boxing Three-Judge Decision Simulator",
    "description": "Enter three official cards and get the correct verdict — unanimous, split, majority, or draw. Handles every decision type including the frequently confused majority draw.",
    "category": "Sports",
    "file": "boxing-three-judge-simulator.html",
    "path": "cards/boxing-three-judge-simulator.html"
  },
  {
    "id": "boxing-weight-class-checker-title",
    "name": "boxing-weight-class-checker",
    "title": "⚖️ Boxing Weight Class & Weigh-In Checker",
    "description": "Find the correct division for any weight, check whether a fighter has made the limit, and see rehydration-clause and catchweight implications. Covers all seventeen professional classes.",
    "category": "Sports",
    "file": "boxing-weight-class-checker.html",
    "path": "cards/boxing-weight-class-checker.html"
  },
  {
    "id": "bpm-counter-title",
    "name": "bpm-counter",
    "title": "BPM Tap Counter (Pro)",
    "description": "Instant, free online BPM Tap Counter (Pro) tool. No signup required.",
    "category": "Music & Audio",
    "file": "bpm-counter.html",
    "path": "cards/bpm-counter.html"
  },
  {
    "id": "bra-size-converter-title",
    "name": "bra-size-converter",
    "title": "🎀 Bra Size Converter",
    "description": "Convert UK, US, EU/FR and AU band + cup. Sister sizes keep the same cup volume (one band up, one cup down). Brands still vary — treat this as a starting letter, not a fitting.",
    "category": "Productivity & Lifestyle",
    "file": "bra-size-converter.html",
    "path": "cards/bra-size-converter.html"
  },
  {
    "id": "braille-alphabet-trainer-title",
    "name": "braille-alphabet-trainer",
    "title": "🔵 Braille Alphabet Trainer",
    "description": "Learn the 26 letters of English Braille by building cells dot by dot and decoding them. Each letter is a 2×3 grid of raised dots — once you see the pattern, the whole alphabet unfolds. All local, n...",
    "category": "Writing & Language",
    "file": "braille-alphabet-trainer.html",
    "path": "cards/braille-alphabet-trainer.html"
  },
  {
    "id": "brand-logo-mark-generator-title",
    "name": "brand-logo-mark-generator",
    "title": "✒️ Brand Mark Forge",
    "description": "Design a real logo in the browser and leave with the vector file. Twenty-two hand-drawn icons, five type treatments, four container shapes, gradient or flat colour, and exports as SVG, a 1024px PNG...",
    "category": "SaaS & Business Killers",
    "file": "brand-logo-mark-generator.html",
    "path": "cards/brand-logo-mark-generator.html"
  },
  {
    "id": "break-even-title",
    "name": "break-even",
    "title": "Break‑Even Calculator",
    "description": "Quick Examples:",
    "category": "Finance & Money",
    "file": "break-even.html",
    "path": "cards/break-even.html"
  },
  {
    "id": "breaker-sizing-title",
    "name": "breaker-sizing",
    "title": "⚡ Breaker Sizing Calculator",
    "description": "Quick Examples:",
    "category": "Science & Engineering",
    "file": "breaker-sizing.html",
    "path": "cards/breaker-sizing.html"
  },
  {
    "id": "brick-calculator-title",
    "name": "brick-calculator",
    "title": "🧱 Brick Calculator",
    "description": "Calculate how many bricks you need for any wall — including mortar joints, waste, and pallets to order. Works for UK standard, metric, and imperial bricks.",
    "category": "Home & DIY",
    "file": "brick-calculator.html",
    "path": "cards/brick-calculator.html"
  },
  {
    "id": "british-monarchs-quiz-title",
    "name": "british-monarchs-quiz",
    "title": "👑 British Monarchs Quiz",
    "description": "Name the kings and queens of England, Scotland and the UK from 1066 to today — ten questions per round with streaks.",
    "category": "Museum & Collection",
    "file": "british-monarchs-quiz.html",
    "path": "cards/british-monarchs-quiz.html"
  },
  {
    "id": "british-regnal-years-title",
    "name": "british-regnal-years",
    "title": "👑 The Regnal Desk",
    "description": "English and British legal years used to be counted from the accession, not 1 January. “3 Geo. III” is the third year of George III’s reign. The desk covers the Hanoverians to the present, plus a Tu...",
    "category": "Museum & Collection",
    "file": "british-regnal-years.html",
    "path": "cards/british-regnal-years.html"
  },
  {
    "id": "budget-title",
    "name": "budget",
    "title": "💰 Financial Budget Dashboard",
    "description": "Smart budgeting with predictive analytics, financial health scoring, and personalized optimization strategies.",
    "category": "Finance & Money",
    "file": "budget.html",
    "path": "cards/budget.html"
  },
  {
    "id": "buffons-needle-pi-title",
    "name": "buffons-needle-pi",
    "title": "🎲 Buffon's Needle π",
    "description": "In 1777 Buffon realised you can measure π by dropping needles on floorboards. Watch the probability of a needle crossing a line converge on 2/π — π again, this time from pure geometry and ...",
    "category": "Mind-Blowing Demos",
    "file": "buffons-needle-pi.html",
    "path": "cards/buffons-needle-pi.html"
  },
  {
    "id": "builders-workmate-title",
    "name": "builders-workmate",
    "title": "🔨 Virtual Builder's Workmate",
    "description": "Virtual measurement and leveling tools using device sensors. Requires camera and motion sensor permissions.",
    "category": "Science & Engineering",
    "file": "builders-workmate.html",
    "path": "cards/builders-workmate.html"
  },
  {
    "id": "business-card-size-guide-title",
    "name": "business-card-size-guide",
    "title": "💳 Business Card Size Guide",
    "description": "Print sizes and pixels for UK/EU (85 × 55 mm), US (3.5 × 2 in), Japanese and Chinese cards. Add 3 mm bleed if a printer asks for it. Not a design studio — just the millimetres they keep getting wrong.",
    "category": "Productivity & Lifestyle",
    "file": "business-card-size-guide.html",
    "path": "cards/business-card-size-guide.html"
  },
  {
    "id": "business-days-working-days-calculator-title",
    "name": "business-days-working-days-calculator",
    "title": "📅 Business Days Calculator",
    "description": "Count weekdays between two dates, or add N working days to a start date. Weekends are skipped; paste extra holidays if you need them. All counting stays on this device.",
    "category": "Finance & Money",
    "file": "business-days-working-days-calculator.html",
    "path": "cards/business-days-working-days-calculator.html"
  },
  {
    "id": "business-model-canvas-builder-title",
    "name": "business-model-canvas-builder",
    "title": "🧩 Business Model Canvas",
    "description": "The one-page strategy board that consultants charge a day rate to facilitate. Fill the nine blocks of a Business Model Canvas or a Lean Canvas, get prompted when a block is too thin to be true, and...",
    "category": "SaaS & Business Killers",
    "file": "business-model-canvas-builder.html",
    "path": "cards/business-model-canvas-builder.html"
  },
  {
    "id": "business-writing-title",
    "name": "business-writing",
    "title": "Business Writing Assistant",
    "description": "Draft clear, professional business documents: memos, executive summaries, proposals, and meeting notes. Choose the document type, enter the purpose and key points, then generate a polished draft yo...",
    "category": "Writing & Language",
    "file": "business-writing.html",
    "path": "cards/business-writing.html"
  },
  {
    "id": "bytes-kb-mb-gb-converter-title",
    "name": "bytes-kb-mb-gb-converter",
    "title": "💾 Bytes ⇄ KB ⇄ MB ⇄ GB",
    "description": "Convert file sizes with SI (1000) or binary IEC (1024) prefixes. Hard-drive boxes use decimal GB; Windows historically used 1024 and still called them GB. Edit any field.",
    "category": "Algorithms & Computer Science",
    "file": "bytes-kb-mb-gb-converter.html",
    "path": "cards/bytes-kb-mb-gb-converter.html"
  },
  {
    "id": "cabin-bag-airline-size-checker-title",
    "name": "cabin-bag-airline-size-checker",
    "title": "🧳 Cabin Bag Size Checker",
    "description": "Type your suitcase in centimetres and see which common airlines it should fit, including wheels and handles as the airline measures them. Limits change — confirm on the carrier’s site before you fly.",
    "category": "Productivity & Lifestyle",
    "file": "cabin-bag-airline-size-checker.html",
    "path": "cards/cabin-bag-airline-size-checker.html"
  },
  {
    "id": "cable-length-title",
    "name": "cable-length",
    "title": "⚡ Cable Length & Voltage Drop",
    "description": "Common Scenarios:",
    "category": "Science & Engineering",
    "file": "cable-length.html",
    "path": "cards/cable-length.html"
  },
  {
    "id": "caffeine-half-life-bedtime-check-title",
    "name": "caffeine-half-life-bedtime-check",
    "title": "☕ Will You Sleep Tonight? (Caffeine Check)",
    "description": "Caffeine has a half-life of roughly five hours, which is why the 4pm espresso is still in your system at midnight. Log what you drank and when, and find out how much will still be circulating at be...",
    "category": "Productivity & Lifestyle",
    "file": "caffeine-half-life-bedtime-check.html",
    "path": "cards/caffeine-half-life-bedtime-check.html"
  },
  {
    "id": "cagr-annual-growth-calculator-title",
    "name": "cagr-annual-growth-calculator",
    "title": "📈 CAGR — Compound Annual Growth",
    "description": "CAGR = (end ÷ start)1/years − 1. The smoothed yearly rate that takes a starting value to an ending value. It ignores deposits, fees and the bumpy path in between — a sketch, not a forecast.",
    "category": "Finance & Money",
    "file": "cagr-annual-growth-calculator.html",
    "path": "cards/cagr-annual-growth-calculator.html"
  },
  {
    "id": "calculus-title",
    "name": "calculus",
    "title": "Calculus Helper",
    "description": "Work with derivatives and integrals. Enter a function of x, choose operation, and generate step‑by‑step results.",
    "category": "Mathematics",
    "file": "calculus.html",
    "path": "cards/calculus.html"
  },
  {
    "id": "calorie-deficit-weight-loss-timeline-title",
    "name": "calorie-deficit-weight-loss-timeline",
    "title": "📉 Calorie Deficit Timeline",
    "description": "Rough weeks to a goal weight from a daily calorie deficit. Uses ~7,700 kcal per kg (about 3,500 kcal per lb). Real bodies adapt — this is a sketch, not a promise, and not medical advice.",
    "category": "Health & Fitness",
    "file": "calorie-deficit-weight-loss-timeline.html",
    "path": "cards/calorie-deficit-weight-loss-timeline.html"
  },
  {
    "id": "calorie-title",
    "name": "calorie",
    "title": "Calorie Calculator",
    "description": "Estimate daily calorie needs with BMR calculation, weight goals, and macronutrient breakdown. Auto-saves profiles for quick access.",
    "category": "Health & Fitness",
    "file": "calorie.html",
    "path": "cards/calorie.html"
  },
  {
    "id": "candy-sugar-stages-calculator-title",
    "name": "candy-sugar-stages-calculator",
    "title": "🍬 Candy & Sugar Stages Guide",
    "description": "Confectionery science & sugar crystallization guide. Features automatic boiling-point elevation correction, cold-water ball test simulations, and invert sugar balancing.",
    "category": "Culinary & Food Science",
    "file": "candy-sugar-stages-calculator.html",
    "path": "cards/candy-sugar-stages-calculator.html"
  },
  {
    "id": "capacitor-calculator-title",
    "name": "capacitor-calculator",
    "title": "Capacitor Calculator",
    "description": "Calculate capacitor values, RC time constants, impedance, and filter characteristics. ⚠️ Educational only — verify with datasheets and professional standards.",
    "category": "Science & Engineering",
    "file": "capacitor-calculator.html",
    "path": "cards/capacitor-calculator.html"
  },
  {
    "id": "capo-calculator-title",
    "name": "capo-calculator",
    "title": "🎸 Capo Calculator",
    "description": "Find capo placement for key transposition, chord conversion, and song adaptation. Supports sharps/flats, multiple fret options, and tuning adjustments.",
    "category": "Music & Audio",
    "file": "capo-calculator.html",
    "path": "cards/capo-calculator.html"
  },
  {
    "id": "car-care-tracker-title",
    "name": "car-care-tracker",
    "title": "🚗 Car Care & MOT Due-Date Tracker",
    "description": "Keeps the dates that are easy to miss and expensive to miss in one place: MOT, tax, insurance, service intervals, and the four items that actually cause MOT failures. Saved in your browser only — n...",
    "category": "Home & DIY",
    "file": "car-care-tracker.html",
    "path": "cards/car-care-tracker.html"
  },
  {
    "id": "car-ownership-cost-calculator-title",
    "name": "car-ownership-cost-calculator",
    "title": "🚗 Car Ownership Cost Calculator (UK)",
    "description": "Work out the true cost of running a car in the UK — depreciation, fuel or electricity, insurance, VED road tax, servicing, MOT, tyres and repairs — per month and per mile. Everything calculates loc...",
    "category": "Finance & Money",
    "file": "car-ownership-cost-calculator.html",
    "path": "cards/car-ownership-cost-calculator.html"
  },
  {
    "id": "carbon-14-dating-calculator-title",
    "name": "carbon-14-dating-calculator",
    "title": "🦴 The Radiocarbon Laboratory",
    "description": "Willard Libby’s clock, as a working exhibit. Living tissue is in equilibrium with atmospheric ¹⁴C; after death the isotope decays with a half-life of 5,730 years (Cambridge). Enter remaining fracti...",
    "category": "Science & Engineering",
    "file": "carbon-14-dating-calculator.html",
    "path": "cards/carbon-14-dating-calculator.html"
  },
  {
    "id": "careerpath-title",
    "name": "careerpath",
    "title": "Career Path Planner",
    "description": "Map out your career goals, milestones, and track progress over time. Save and manage multiple career plans.",
    "category": "Productivity & Lifestyle",
    "file": "careerpath.html",
    "path": "cards/careerpath.html"
  },
  {
    "id": "carer-respite-planner-title",
    "name": "carer-respite-planner",
    "title": "🫂 Carer's Respite Planner",
    "description": "Most carers never get a break, and it is rarely because nobody wants to help. It is because the carer is the only person who knows what needs doing. This turns what is in your head into a handover ...",
    "category": "Wellbeing & Community",
    "file": "carer-respite-planner.html",
    "path": "cards/carer-respite-planner.html"
  },
  {
    "id": "carol-karaoke-title",
    "name": "carol-karaoke",
    "title": "🎵 Christmas Carol Karaoke Machine",
    "description": "Sing along to Christmas classics with synchronized lyrics, pitch detection, and festive backgrounds! 🎤 Features: 50+ carols, pitch meter, key changer, duet mode, recording",
    "category": "Music & Audio",
    "file": "carol-karaoke.html",
    "path": "cards/carol-karaoke.html"
  },
  {
    "id": "cartographers-world-forge-title",
    "name": "cartographers-world-forge",
    "title": "🗺️ Cartographer's World Forge",
    "description": "Forge an entire fantasy world from a single seed. Tectonic uplift raises mountains, rain shadows carve deserts, rivers find the sea, and civilisations rise where the land is kind. Every kingdom, to...",
    "category": "Productivity & Lifestyle",
    "file": "cartographers-world-forge.html",
    "path": "cards/cartographers-world-forge.html"
  },
  {
    "id": "case-converter-title",
    "name": "case-converter",
    "title": "🔤 Case Converter",
    "description": "Convert text between uppercase, lowercase, title case, sentence case, and more. Instant transformation.",
    "category": "Algorithms & Computer Science",
    "file": "case-converter.html",
    "path": "cards/case-converter.html"
  },
  {
    "id": "cash-runway-planner-title",
    "name": "cash-runway-planner",
    "title": "🏃 Cash Runway Planner",
    "description": "Forecast how long business cash will last and the revenue or cost change needed to reach a target runway. All calculations stay in your browser.",
    "category": "Finance & Money",
    "file": "cash-runway-planner.html",
    "path": "cards/cash-runway-planner.html"
  },
  {
    "id": "cat-photo-viewer-title",
    "name": "cat-photo-viewer",
    "title": "Cat Photo Viewer",
    "description": "Browse cat photos from free public APIs. Features infinite scrolling, favorites, and breed info.",
    "category": "Productivity & Lifestyle",
    "file": "cat-photo-viewer.html",
    "path": "cards/cat-photo-viewer.html"
  },
  {
    "id": "cellular-automata-explorer-title",
    "name": "cellular-automata-explorer",
    "title": "🔲 Cellular Automata Explorer",
    "description": "One row of cells and one rule decides the next row from each cell's three neighbours. Rule 30 churns out pure randomness, Rule 90 grows a Sierpinski triangle, and Rule 110 is powerful enough to com...",
    "category": "Algorithms & Computer Science",
    "file": "cellular-automata-explorer.html",
    "path": "cards/cellular-automata-explorer.html"
  },
  {
    "id": "celsius-fahrenheit-kelvin-converter-title",
    "name": "celsius-fahrenheit-kelvin-converter",
    "title": "🌡️ Celsius ⇄ Fahrenheit ⇄ Kelvin",
    "description": "°F = °C × 9/5 + 32. Kelvin = °C + 273.15. Absolute zero is 0 K (−273.15 °C). Edit any box — weather, ovens and science labs all use different scales.",
    "category": "Science & Engineering",
    "file": "celsius-fahrenheit-kelvin-converter.html",
    "path": "cards/celsius-fahrenheit-kelvin-converter.html"
  },
  {
    "id": "censorship-monitor-title",
    "name": "censorship-monitor",
    "title": "🌐 Censorship Monitor",
    "description": "Monitor Wikipedia blocks and Reddit content moderation in real-time. ⚠️ Educational tool - uses public APIs",
    "category": "Productivity & Lifestyle",
    "file": "censorship-monitor.html",
    "path": "cards/censorship-monitor.html"
  },
  {
    "id": "chaotic-magnetic-pendulum-title",
    "name": "chaotic-magnetic-pendulum",
    "title": "🧭 Chaotic Magnetic Pendulum",
    "description": "Nonlinear chaos theory exhibit. A metallic pendulum swings over three magnetic attractors, demonstrating sensitive dependence on initial conditions.",
    "category": "Science & Engineering",
    "file": "chaotic-magnetic-pendulum.html",
    "path": "cards/chaotic-magnetic-pendulum.html"
  },
  {
    "id": "character-limit-platform-counter-title",
    "name": "character-limit-platform-counter",
    "title": "🔤 Platform Character Counter",
    "description": "Count characters against the live limits for X/Twitter, SMS, Google titles, Instagram, LinkedIn and more. Everything stays in this box — no draft is uploaded.",
    "category": "Writing & Language",
    "file": "character-limit-platform-counter.html",
    "path": "cards/character-limit-platform-counter.html"
  },
  {
    "id": "chemical-solution-dilution-title",
    "name": "chemical-solution-dilution",
    "title": "🧪 Solution Dilution Lab",
    "description": "Precision wet-lab chemistry solver for serial dilutions ($C_1 V_1 = C_2 V_2$) and molarity-to-mass conversions ($\\text{Mass} = M \\times V \\times \\text{MW}$) with step-by-step bench pipetting protoc...",
    "category": "Science & Engineering",
    "file": "chemical-solution-dilution.html",
    "path": "cards/chemical-solution-dilution.html"
  },
  {
    "id": "chemistry-title",
    "name": "chemistry",
    "title": "Chemistry Helper",
    "description": "Calculate molar mass, balance equations, analyze compounds, and reference periodic table data.",
    "category": "Productivity & Lifestyle",
    "file": "chemistry.html",
    "path": "cards/chemistry.html"
  },
  {
    "id": "chess-elo-rating-calculator-title",
    "name": "chess-elo-rating-calculator",
    "title": "♟️ Chess Elo Rating Calculator",
    "description": "See what a single game does to a rating. Enter both players' ratings and the result, and this gives the expected score, the exact rating change, the new rating, and the performance rating for that ...",
    "category": "Sports",
    "file": "chess-elo-rating-calculator.html",
    "path": "cards/chess-elo-rating-calculator.html"
  },
  {
    "id": "childgrowth-title",
    "name": "childgrowth",
    "title": "Child Growth Tracker",
    "description": "Track your child's growth, compare with WHO percentiles, and monitor development milestones.",
    "category": "Health & Fitness",
    "file": "childgrowth.html",
    "path": "cards/childgrowth.html"
  },
  {
    "id": "chinese-tones-pinyin-title",
    "name": "chinese-tones-pinyin",
    "title": "🇨🇳 Chinese Tones & Pinyin",
    "description": "Conquer the 4 tonal contours of Mandarin Chinese (High Flat, Rising, Dipping, Falling) and explore foundational HSK 1 vocabulary with native Mandarin speech audio (`zh-CN`).",
    "category": "Writing & Language",
    "file": "chinese-tones-pinyin.html",
    "path": "cards/chinese-tones-pinyin.html"
  },
  {
    "id": "chocolate-tempering-curve-lab-title",
    "name": "chocolate-tempering-curve-lab",
    "title": "🍫 Chocolate Tempering Curves",
    "description": "Cocoa butter polymorphism & Beta-V crystallization guide. Calculates 3-stage thermal curve temperatures, 80/20 seeding ratios, and diagnoses fat bloom versus clean snap.",
    "category": "Culinary & Food Science",
    "file": "chocolate-tempering-curve-lab.html",
    "path": "cards/chocolate-tempering-curve-lab.html"
  },
  {
    "id": "chord-finder-title",
    "name": "chord-finder",
    "title": "🎵 Chord Finder",
    "description": "Identify chords from selected notes. Perfect for songwriters and beginners!",
    "category": "Music & Audio",
    "file": "chord-finder.html",
    "path": "cards/chord-finder.html"
  },
  {
    "id": "chord-progression-title",
    "name": "chord-progression",
    "title": "🎼 Chord Progression Builder",
    "description": "Build, analyze, and explore chord progressions for songwriting. Perfect for musicians and composers!",
    "category": "Music & Audio",
    "file": "chord-progression.html",
    "path": "cards/chord-progression.html"
  },
  {
    "id": "christmas-card-maker-title",
    "name": "christmas-card-maker",
    "title": "🎄 Christmas Card Maker",
    "description": "Design and generate beautiful, custom HTML Christmas cards in seconds. Perfect for emails, social media, or personal websites.",
    "category": "Productivity & Lifestyle",
    "file": "christmas-card-maker.html",
    "path": "cards/christmas-card-maker.html"
  },
  {
    "id": "christmas-naughty-list-quiz-title",
    "name": "christmas-naughty-list-quiz",
    "title": "🎅 Santa's Naughty List Quiz",
    "description": "Take this scientific* holiday quiz to discover if you're getting coal or presents this Christmas! *Not actually scientific",
    "category": "Productivity & Lifestyle",
    "file": "christmas-naughty-list-quiz.html",
    "path": "cards/christmas-naughty-list-quiz.html"
  },
  {
    "id": "chrono-garden-l-system-botany-title",
    "name": "chrono-garden-l-system-botany",
    "title": "🌿 ChronoGarden Terrarium",
    "description": "Cultivate a communal fractal botanical garden over time. Plant mathematical trees using Aristid Lindenmayer's L-Systems, cross-breed genetic strains, watch branches sway in the dynamic breeze, and ...",
    "category": "Interactive Art & Living Worlds",
    "file": "chrono-garden-l-system-botany.html",
    "path": "cards/chrono-garden-l-system-botany.html"
  },
  {
    "id": "circuit-calculator-title",
    "name": "circuit-calculator",
    "title": "🔌 Circuit Calculator",
    "description": "Calculate circuit load, breaker size, and wire sizing. Perfect for DIY projects and planning.",
    "category": "Science & Engineering",
    "file": "circuit-calculator.html",
    "path": "cards/circuit-calculator.html"
  },
  {
    "id": "citation-title",
    "name": "citation",
    "title": "📚 Citation Generator",
    "description": "Generate perfectly formatted citations in APA, MLA, or Chicago style. Supports multiple authors, websites, and academic sources.",
    "category": "Writing & Language",
    "file": "citation.html",
    "path": "cards/citation.html"
  },
  {
    "id": "classical-cipher-suite-title",
    "name": "classical-cipher-suite",
    "title": "🔐 Classical Cipher Suite",
    "description": "Encrypt like the Romans and the Victorians: Caesar shifts, Atbash mirrors, ROT13 and the Vigenère key cipher. Then watch the “crack” button undo a Caesar cipher in one click — because l...",
    "category": "Algorithms & Computer Science",
    "file": "classical-cipher-suite.html",
    "path": "cards/classical-cipher-suite.html"
  },
  {
    "id": "cleaning-title",
    "name": "cleaning",
    "title": "🧹 Cleaning Schedule",
    "description": "Plan, track, and manage cleaning tasks with smart scheduling. Never forget a chore again!",
    "category": "Productivity & Lifestyle",
    "file": "cleaning.html",
    "path": "cards/cleaning.html"
  },
  {
    "id": "climbing-anchor-force-calculator-title",
    "name": "climbing-anchor-force-calculator",
    "title": "🧗 Climbing Anchor Force & Fall Factor Calculator",
    "description": "A falling climber does not load the system with their body weight — they load it with several times that, and the top runner takes more than the climber does. This works out impact force from the f...",
    "category": "Science & Engineering",
    "file": "climbing-anchor-force-calculator.html",
    "path": "cards/climbing-anchor-force-calculator.html"
  },
  {
    "id": "clip-short-title",
    "name": "clip-short",
    "title": "🎬 Clip‑to‑Shorts Repackager",
    "description": "Upload a gameplay clip, pick a segment, and export a perfectly framed vertical short (9:16) or other preset. Adds caption safe zone and optional watermark.",
    "category": "Productivity & Lifestyle",
    "file": "clip-short.html",
    "path": "cards/clip-short.html"
  },
  {
    "id": "clipboard-history-title",
    "name": "clipboard-history",
    "title": "📋 Clipboard History",
    "description": "Save and manage text snippets. Copy, pin, search, and organize your frequently used text. Persists in browser storage.",
    "category": "Productivity & Lifestyle",
    "file": "clipboard-history.html",
    "path": "cards/clipboard-history.html"
  },
  {
    "id": "clock-angle-calculator-title",
    "name": "clock-angle-calculator",
    "title": "🕐 Clock Angle Calculator",
    "description": "Angle between hour and minute hands. Minute hand = 6° × minutes. Hour hand = 0.5° × (60×hours + minutes). The smaller angle is min(θ, 360 − θ).",
    "category": "Mathematics",
    "file": "clock-angle-calculator.html",
    "path": "cards/clock-angle-calculator.html"
  },
  {
    "id": "clock-reading-trainer-title",
    "name": "clock-reading-trainer",
    "title": "🕰️ Clock Reading & Telling Time Trainer",
    "description": "Read the hands, set the clock yourself, and work out elapsed time — three modes, five questions each, with instant feedback. The clock is drawn locally; nothing leaves your device.",
    "category": "Mathematics",
    "file": "clock-reading-trainer.html",
    "path": "cards/clock-reading-trainer.html"
  },
  {
    "id": "clothing-size-converter-title",
    "name": "clothing-size-converter",
    "title": "👕 Clothing Size Converter",
    "description": "Convert common adult clothing sizes between US, UK and EU for tops, dresses and men’s shirts. Charts are industry averages — cut, stretch and brand vanity sizing still win. Measure twice.",
    "category": "Productivity & Lifestyle",
    "file": "clothing-size-converter.html",
    "path": "cards/clothing-size-converter.html"
  },
  {
    "id": "coat-or-no-coat-weather-title",
    "name": "coat-or-no-coat-weather",
    "title": "🧥 Coat, Hoodie, or Regret?",
    "description": "The daily sartorial gamble, solved. Dial in the temperature, wind and rain, tell it how long you'll be out, and it will tell you what to wear — with the correct level of weather-based sass.",
    "category": "Productivity & Lifestyle",
    "file": "coat-or-no-coat-weather.html",
    "path": "cards/coat-or-no-coat-weather.html"
  },
  {
    "id": "coffee-brew-ratio-calculator-title",
    "name": "coffee-brew-ratio-calculator",
    "title": "☕ Coffee Brew Ratio & TDS Lab",
    "description": "Specialty Coffee Association (SCA) Golden Cup extraction calculator. Computes precise dose, brew water yield, multi-stage pour intervals, grind microns, and theoretical extraction yield.",
    "category": "Culinary & Food Science",
    "file": "coffee-brew-ratio-calculator.html",
    "path": "cards/coffee-brew-ratio-calculator.html"
  },
  {
    "id": "cognitive-bias-detector-title",
    "name": "cognitive-bias-detector",
    "title": "🔍 Cognitive Bias Detector",
    "description": "Interrogate any argument, news headline, debate talking point, or internal decision. TruthLens scans text against 24 universal cognitive biases and logical fallacies to sharpen your critical thinki...",
    "category": "Writing & Language",
    "file": "cognitive-bias-detector.html",
    "path": "cards/cognitive-bias-detector.html"
  },
  {
    "id": "coincidence-finder-title",
    "name": "coincidence-finder",
    "title": "🔮 Coincidence Finder & Synchronicity Tracker",
    "description": "Discover meaningful coincidences and synchronicities across multiple real-time data sources. Tracks news, numbers, dates, names, and global patterns!",
    "category": "Productivity & Lifestyle",
    "file": "coincidence-finder.html",
    "path": "cards/coincidence-finder.html"
  },
  {
    "id": "cold-flu-natural-remedy-hub-title",
    "name": "cold-flu-natural-remedy-hub",
    "title": "🍯 Cold & Flu Botanical Guide",
    "description": "Phase-specific botanical recovery matrix. Synchronizes natural remedies to viral replication curves—from neuraminidase inhibitors at hour zero to diaphoretic fever teas and expectorants.",
    "category": "Natural Remedies & Herbs",
    "file": "cold-flu-natural-remedy-hub.html",
    "path": "cards/cold-flu-natural-remedy-hub.html"
  },
  {
    "id": "cold-water-ice-drowning-rescue-title",
    "name": "cold-water-ice-drowning-rescue",
    "title": "🌊 Cold Water, Ice & Drowning Rescue",
    "description": "Cold water kills strong swimmers in minutes, and it kills them long before hypothermia is even possible. Most people who die in UK waters were never trying to swim far — they fell in, gasped, and i...",
    "category": "Survival & Emergency Readiness",
    "file": "cold-water-ice-drowning-rescue.html",
    "path": "cards/cold-water-ice-drowning-rescue.html"
  },
  {
    "id": "collaboration-title",
    "name": "collaboration",
    "title": "🤖 AI Team Hub",
    "description": "AI-powered team management with workload balancing, predictive analytics, and automated optimization. ⚡ Smart suggestions • 🎯 Predictive deadlines • 📊 Real-time analytics",
    "category": "Productivity & Lifestyle",
    "file": "collaboration.html",
    "path": "cards/collaboration.html"
  },
  {
    "id": "color-contrast-checker-title",
    "name": "color-contrast-checker",
    "title": "🎨 Color Contrast Checker",
    "description": "Check color contrast ratios for WCAG accessibility compliance. Test foreground and background colors for text readability.",
    "category": "Algorithms & Computer Science",
    "file": "color-contrast-checker.html",
    "path": "cards/color-contrast-checker.html"
  },
  {
    "id": "color-contrast-wcag-simulator-title",
    "name": "color-contrast-wcag-simulator",
    "title": "👁️ WCAG Contrast & Vision",
    "description": "Test color contrast ratios against WCAG 2.2 accessibility standards (AA / AAA) and simulate color-vision deficiencies in real time.",
    "category": "Productivity & Lifestyle",
    "file": "color-contrast-wcag-simulator.html",
    "path": "cards/color-contrast-wcag-simulator.html"
  },
  {
    "id": "color-converter-harmony-studio-title",
    "name": "color-converter-harmony-studio",
    "title": "🎨 Color Converter & Palette Harmony Studio",
    "description": "Convert between HEX, RGB, HSL, HSV, CMYK, and OKLCH color spaces, generate color harmonies, test WCAG 2.1 contrast ratios, and copy CSS color code.",
    "category": "Productivity & Lifestyle",
    "file": "color-converter-harmony-studio.html",
    "path": "cards/color-converter-harmony-studio.html"
  },
  {
    "id": "color-harmony-palette-generator-title",
    "name": "color-harmony-palette-generator",
    "title": "🎨 Colour Harmony Palette",
    "description": "Complementary, analogous, triadic and split-complement palettes from one hex colour. Hue is rotated on the HSL wheel; saturation and lightness stay put. For contrast of text on a fill, use the WCAG...",
    "category": "Productivity & Lifestyle",
    "file": "color-harmony-palette-generator.html",
    "path": "cards/color-harmony-palette-generator.html"
  },
  {
    "id": "color-hex-rgb-hsl-converter-title",
    "name": "color-hex-rgb-hsl-converter",
    "title": "🎨 Colour Converter HEX RGB HSL",
    "description": "Convert any colour between HEX, RGB, HSL, HSV and CMYK, with a live swatch and one-click copy. Parsing is local — no eyedropper upload, no network.",
    "category": "Productivity & Lifestyle",
    "file": "color-hex-rgb-hsl-converter.html",
    "path": "cards/color-hex-rgb-hsl-converter.html"
  },
  {
    "id": "color-palette-extractor-title",
    "name": "color-palette-extractor",
    "title": "🎨 Color Palette Extractor",
    "description": "Generate algorithmic color harmonies (Complementary, Triadic, Analogous, Split) and verify accessibility with real-time WCAG 2.1 AA/AAA contrast ratio verification.",
    "category": "Science & Engineering",
    "file": "color-palette-extractor.html",
    "path": "cards/color-palette-extractor.html"
  },
  {
    "id": "color-picker-converter-title",
    "name": "color-picker-converter",
    "title": "🎨 Color Picker & Converter",
    "description": "Pick colors visually and convert between HEX, RGB, HSL, and HSV formats. Generate palettes and copy values instantly.",
    "category": "Productivity & Lifestyle",
    "file": "color-picker-converter.html",
    "path": "cards/color-picker-converter.html"
  },
  {
    "id": "color-picker-hex-rgb-hsl-converter-title",
    "name": "color-picker-hex-rgb-hsl-converter",
    "title": "🎨 Colour Picker & HEX / RGB / HSL Converter",
    "description": "Pick a colour or paste any CSS colour (HEX, RGB, HSL, or a named colour) and get every format back instantly — plus tints, shades, complementary and triadic harmonies, and the WCAG contrast ratio a...",
    "category": "Productivity & Lifestyle",
    "file": "color-picker-hex-rgb-hsl-converter.html",
    "path": "cards/color-picker-hex-rgb-hsl-converter.html"
  },
  {
    "id": "common-english-mistakes-trainer-title",
    "name": "common-english-mistakes-trainer",
    "title": "✏️ Common English Mistakes Trainer",
    "description": "Fix the most common English errors — its/it's, there/their, affect/effect and more — one sentence at a time.",
    "category": "Writing & Language",
    "file": "common-english-mistakes-trainer.html",
    "path": "cards/common-english-mistakes-trainer.html"
  },
  {
    "id": "commute-title",
    "name": "commute",
    "title": "🚗 Commute Calculator",
    "description": "Calculate commute time, cost, and environmental impact. Compare different transportation modes. ✅ Tracks daily, weekly, monthly, and yearly totals",
    "category": "Productivity & Lifestyle",
    "file": "commute.html",
    "path": "cards/commute.html"
  },
  {
    "id": "compass-bearings-trainer-title",
    "name": "compass-bearings-trainer",
    "title": "🧭 Compass Bearings Trainer",
    "description": "Learn the 16-point compass rose: convert between named bearings and degrees, then practise reading them on a marked compass — forward and back bearings, with instant feedback. All local, no tracking.",
    "category": "Science & Engineering",
    "file": "compass-bearings-trainer.html",
    "path": "cards/compass-bearings-trainer.html"
  },
  {
    "id": "complex-numbers-title",
    "name": "complex-numbers",
    "title": "🧮 Complex Numbers Calculator",
    "description": "Perform operations with complex numbers in rectangular (a+bi) and polar (r∠θ) forms. Visualize results on the complex plane with step-by-step solutions. ✅ Supports: + − × ÷ √ ^ log sin cos conjugat...",
    "category": "Mathematics",
    "file": "complex-numbers.html",
    "path": "cards/complex-numbers.html"
  },
  {
    "id": "compoundinterest-title",
    "name": "compoundinterest",
    "title": "💰 Compound Interest Calculator",
    "description": "Calculate future value, growth projections, and compare investment scenarios. Visualize wealth accumulation over time with detailed breakdowns. ✅ Features: Regular contributions, inflation adjustme...",
    "category": "Finance & Money",
    "file": "compoundinterest.html",
    "path": "cards/compoundinterest.html"
  },
  {
    "id": "concrete-mix-calculator-title",
    "name": "concrete-mix-calculator",
    "title": "🧱 Concrete Mix Calculator",
    "description": "Calculate cement, sand, gravel, and water for any concrete project — from fence posts to shed bases.",
    "category": "Home & DIY",
    "file": "concrete-mix-calculator.html",
    "path": "cards/concrete-mix-calculator.html"
  },
  {
    "id": "conduit-sizing-title",
    "name": "conduit-sizing",
    "title": "⚡ Conduit Sizing Calculator",
    "description": "Calculate conduit sizes based on NEC requirements, wire types, and installation conditions. ⚠️ Disclaimer: For educational purposes. Always consult NEC codebook and licensed electrician.",
    "category": "Science & Engineering",
    "file": "conduit-sizing.html",
    "path": "cards/conduit-sizing.html"
  },
  {
    "id": "conservation-lux-hours-title",
    "name": "conservation-lux-hours",
    "title": "💡 The Light Budget",
    "description": "Light is a loan with interest. Museums cap both instant lux and lux-hours per year. Pick a material class, the gallery level and the hours the case is lit. The plaque says whether the year is still...",
    "category": "Science & Engineering",
    "file": "conservation-lux-hours.html",
    "path": "cards/conservation-lux-hours.html"
  },
  {
    "id": "conspiracy-theory-generator-title",
    "name": "conspiracy-theory-generator",
    "title": "🤡 Conspiracy Theory Generator",
    "description": "Generate absurd conspiracy theories that are somehow more believable than the real ones.",
    "category": "Productivity & Lifestyle",
    "file": "conspiracy-theory-generator.html",
    "path": "cards/conspiracy-theory-generator.html"
  },
  {
    "id": "constant-treasury-title",
    "name": "constant-treasury",
    "title": "📐 The Constant Treasury",
    "description": "The constants that run the universe, as numbered exhibits — provenance, exact or measured, and what each does. Includes a live pi engine (Machin's formula computed with big integers), a golden-rati...",
    "category": "Museum & Collection",
    "file": "constant-treasury.html",
    "path": "cards/constant-treasury.html"
  },
  {
    "id": "constellation-chronicle-star-weaver-title",
    "name": "constellation-chronicle-star-weaver",
    "title": "✨ Constellation Weaver",
    "description": "Weave constellations across a shared celestial sphere. Place spectral stars, connect mythological asterisms, record astronomical lore, and preserve collective starlit storytelling over time.",
    "category": "Interactive Art & Living Worlds",
    "file": "constellation-chronicle-star-weaver.html",
    "path": "cards/constellation-chronicle-star-weaver.html"
  },
  {
    "id": "conways-game-of-life-title",
    "name": "conways-game-of-life",
    "title": "🧬 Conway's Game of Life",
    "description": "Three tiny rules, no designer, and yet gliders, blinkers and whole ecosystems appear. Click cells to seed life, then watch a universe build itself from nothing.",
    "category": "Mind-Blowing Demos",
    "file": "conways-game-of-life.html",
    "path": "cards/conways-game-of-life.html"
  },
  {
    "id": "cooking-time-adjuster-title",
    "name": "cooking-time-adjuster",
    "title": "⏱️ Cooking Time Adjuster",
    "description": "PROFESSIONAL TOOL - Adjust cooking times when scaling recipes, changing pan sizes, or cooking at different temperatures. Used by chefs and home cooks worldwide.",
    "category": "Culinary & Food Science",
    "file": "cooking-time-adjuster.html",
    "path": "cards/cooking-time-adjuster.html"
  },
  {
    "id": "cooking-unit-converter-title",
    "name": "cooking-unit-converter",
    "title": "🥄 Cooking Unit Converter",
    "description": "PROFESSIONAL CONVERTER - Convert cooking units with food-specific densities. Accurate conversions for flour, sugar, butter, liquids, and more.",
    "category": "Culinary & Food Science",
    "file": "cooking-unit-converter.html",
    "path": "cards/cooking-unit-converter.html"
  },
  {
    "id": "coordinate-format-translator-title",
    "name": "coordinate-format-translator",
    "title": "🧭 Coordinate Format Translator",
    "description": "One position, every notation: decimal degrees, degrees-minutes-seconds, marine DDM, UTM, MGRS, the British Ordnance Survey grid, geohash, Plus Code and the Maidenhead locator used by radio amateurs...",
    "category": "Science & Engineering",
    "file": "coordinate-format-translator.html",
    "path": "cards/coordinate-format-translator.html"
  },
  {
    "id": "coordinates-trainer-title",
    "name": "coordinates-trainer",
    "title": "📈 Coordinates Trainer",
    "description": "Read points and plot your own on a −5 to +5 grid. Learn the four quadrants, the meaning of (x, y) and how negative coordinates work — with instant feedback and 5-question rounds. All on your device.",
    "category": "MrProphecy Arcade",
    "file": "coordinates-trainer.html",
    "path": "cards/coordinates-trainer.html"
  },
  {
    "id": "cors-header-builder-title",
    "name": "cors-header-builder",
    "title": "🌐 CORS Header Builder",
    "description": "Emit Access-Control-* headers for a simple or preflight response. * plus credentials is invalid. Prefer an explicit origin in production.",
    "category": "Algorithms & Computer Science",
    "file": "cors-header-builder.html",
    "path": "cards/cors-header-builder.html"
  },
  {
    "id": "cosmic-ray-cloud-chamber-title",
    "name": "cosmic-ray-cloud-chamber",
    "title": "🌫️ Wilson Cloud Chamber",
    "description": "Supersaturated alcohol vapor chamber detecting cosmic muons and subatomic radioactive decay tracks via ion-nucleated condensation.",
    "category": "Science & Engineering",
    "file": "cosmic-ray-cloud-chamber.html",
    "path": "cards/cosmic-ray-cloud-chamber.html"
  },
  {
    "id": "cost-per-use-buy-or-not-title",
    "name": "cost-per-use-buy-or-not",
    "title": "🛒 Cost-Per-Use: Should You Buy It?",
    "description": "The antidote to impulse buying. Feed it a price and honest usage guesses, and it tells you whether that thing is a bargain, a luxury, or a future eBay listing.",
    "category": "Productivity & Lifestyle",
    "file": "cost-per-use-buy-or-not.html",
    "path": "cards/cost-per-use-buy-or-not.html"
  },
  {
    "id": "countdown-timer-stopwatch-laps-title",
    "name": "countdown-timer-stopwatch-laps",
    "title": "⏳ Countdown Timer & Stopwatch with Laps",
    "description": "A precise stopwatch with lap splits and a countdown timer with presets, keyboard shortcuts (Space = start/stop, L = lap, R = reset) and a gentle beep when the countdown finishes. Keeps accurate tim...",
    "category": "Productivity & Lifestyle",
    "file": "countdown-timer-stopwatch-laps.html",
    "path": "cards/countdown-timer-stopwatch-laps.html"
  },
  {
    "id": "country-flags-quiz-title",
    "name": "country-flags-quiz",
    "title": "🚩 Country Flags Quiz",
    "description": "Guess the country from its flag, or pick the right flag for a named country — with three difficulty pools, ten questions per round and colour-based clues. All drawn locally, nothing sent anywhere.",
    "category": "MrProphecy Arcade",
    "file": "country-flags-quiz.html",
    "path": "cards/country-flags-quiz.html"
  },
  {
    "id": "coupled-oscillators-normal-modes-title",
    "name": "coupled-oscillators-normal-modes",
    "title": "🎛️ Coupled Oscillators Lab",
    "description": "Simulate multi-degree-of-freedom coupled mechanical oscillators. Observe symmetric ($\\omega_1$) vs anti-symmetric ($\\omega_2$) normal modes and cyclic mechanical energy sloshing ($T_{beat}$).",
    "category": "Science & Engineering",
    "file": "coupled-oscillators-normal-modes.html",
    "path": "cards/coupled-oscillators-normal-modes.html"
  },
  {
    "id": "cover-letter-title",
    "name": "cover-letter",
    "title": "✍️ Cover Letter Builder",
    "description": "PROFESSIONAL TOOL - Create tailored cover letters with industry-specific templates, ATS optimization, and professional tone analysis. Used by career coaches worldwide.",
    "category": "Writing & Language",
    "file": "cover-letter.html",
    "path": "cards/cover-letter.html"
  },
  {
    "id": "creative-writing-title",
    "name": "creative-writing",
    "title": "Creative Writing",
    "description": "Instant, free online Creative Writing tool. No signup required.",
    "category": "Writing & Language",
    "file": "creative-writing.html",
    "path": "cards/creative-writing.html"
  },
  {
    "id": "creditcard-title",
    "name": "creditcard",
    "title": "💳 Credit Card Calculator",
    "description": "Calculate how long it will take to pay off your credit card and save money with different payoff strategies.",
    "category": "Finance & Money",
    "file": "creditcard.html",
    "path": "cards/creditcard.html"
  },
  {
    "id": "cricket-chase-calculator-title",
    "name": "cricket-chase-calculator",
    "title": "🏏 Cricket Run-Chase Calculator",
    "description": "Second innings, chasing a target: enter the score you are after, how far the chase has got, and see the current rate, the required rate, your projected total, and exactly how fast the run rate has ...",
    "category": "Sports",
    "file": "cricket-chase-calculator.html",
    "path": "cards/cricket-chase-calculator.html"
  },
  {
    "id": "cricket-net-run-rate-calculator-title",
    "name": "cricket-net-run-rate-calculator",
    "title": "🏏 Cricket Net Run Rate Calculator",
    "description": "The tie-breaker that decides tournaments. Add each match's runs and overs for and against, and this works out your aggregate Net Run Rate — applying the rule that a team bowled out is counted as fa...",
    "category": "Sports",
    "file": "cricket-net-run-rate-calculator.html",
    "path": "cards/cricket-net-run-rate-calculator.html"
  },
  {
    "id": "crisis-offline-triage-title",
    "name": "crisis-offline-triage",
    "title": "🆘 Crisis Triage Guide",
    "description": "100% offline emergency triage protocols, acoustic CPR rhythm metronome, water survival calculator, and optical SOS distress beacon. Operates completely without internet during grid blackouts and na...",
    "category": "Health & Fitness",
    "file": "crisis-offline-triage.html",
    "path": "cards/crisis-offline-triage.html"
  },
  {
    "id": "cron-expression-builder-title",
    "name": "cron-expression-builder",
    "title": "⏰ Cron Expression Builder",
    "description": "Visually build cron expressions. Select when to run, see the expression update live. Includes presets, next run preview, and human-readable description.",
    "category": "Algorithms & Computer Science",
    "file": "cron-expression-builder.html",
    "path": "cards/cron-expression-builder.html"
  },
  {
    "id": "cron-schedule-expression-builder-title",
    "name": "cron-schedule-expression-builder",
    "title": "⏱️ Cron Schedule Builder",
    "description": "Construct cron expressions with interactive dials, read instant plain-English explanations, and preview the next 10 trigger times.",
    "category": "Productivity & Lifestyle",
    "file": "cron-schedule-expression-builder.html",
    "path": "cards/cron-schedule-expression-builder.html"
  },
  {
    "id": "crop-factor-35mm-equivalent-title",
    "name": "crop-factor-35mm-equivalent",
    "title": "🖼️ Crop Factor & 35 mm Equivalent",
    "description": "35 mm-equivalent focal length = actual focal length × crop factor. Also shows equivalent f-number for depth of field (same framing). Field of view matches; light-gathering of the aperture does not ...",
    "category": "Productivity & Lifestyle",
    "file": "crop-factor-35mm-equivalent.html",
    "path": "cards/crop-factor-35mm-equivalent.html"
  },
  {
    "id": "css-animation-generator-title",
    "name": "css-animation-generator",
    "title": "✨ CSS Animation Generator",
    "description": "Preview common CSS keyframe animations, tune duration, delay and easing, then copy a small standalone animation block. The preview honours reduced-motion preferences; use motion as polish, never as...",
    "category": "SaaS & Business Killers",
    "file": "css-animation-generator.html",
    "path": "cards/css-animation-generator.html"
  },
  {
    "id": "css-border-radius-generator-title",
    "name": "css-border-radius-generator",
    "title": "🔘 CSS Border Radius Generator",
    "description": "Shape a card, button or image frame with four independent corner radii, preview the result and copy the compact CSS shorthand. Switch between pixels and percentages, link corners while you explore,...",
    "category": "SaaS & Business Killers",
    "file": "css-border-radius-generator.html",
    "path": "cards/css-border-radius-generator.html"
  },
  {
    "id": "css-box-shadow-generator-title",
    "name": "css-box-shadow-generator",
    "title": "🌑 CSS Box Shadow Generator",
    "description": "Tune a CSS box-shadow visually, choose a colour and opacity, test inset mode and copy production-ready CSS. The preview updates as you move the controls, so there is no design account or upload step.",
    "category": "SaaS & Business Killers",
    "file": "css-box-shadow-generator.html",
    "path": "cards/css-box-shadow-generator.html"
  },
  {
    "id": "css-filter-generator-title",
    "name": "css-filter-generator",
    "title": "🎛️ CSS Filter Generator",
    "description": "Combine brightness, contrast, saturation, hue, blur and monochrome effects with a live visual preview, then copy one filter declaration. Useful for hero images, hover states and quick image treatme...",
    "category": "SaaS & Business Killers",
    "file": "css-filter-generator.html",
    "path": "cards/css-filter-generator.html"
  },
  {
    "id": "css-flexbox-playground-title",
    "name": "css-flexbox-playground",
    "title": "↔️ CSS Flexbox Playground",
    "description": "Explore real flexbox controls side by side: direction, wrapping, gap and alignment update the preview immediately, then a copyable CSS block records the exact settings. Use it to build nav rows, ce...",
    "category": "SaaS & Business Killers",
    "file": "css-flexbox-playground.html",
    "path": "cards/css-flexbox-playground.html"
  },
  {
    "id": "css-glassmorphism-gradient-generator-title",
    "name": "css-glassmorphism-gradient-generator",
    "title": "🎨 CSS Glass & Gradients",
    "description": "Design modern frosted glass (glassmorphism) components and mesh gradients. Real-time visual canvas with 1-click cross-browser CSS.",
    "category": "Productivity & Lifestyle",
    "file": "css-glassmorphism-gradient-generator.html",
    "path": "cards/css-glassmorphism-gradient-generator.html"
  },
  {
    "id": "css-grid-layout-generator-title",
    "name": "css-grid-layout-generator",
    "title": "🔲 CSS Grid Layout Generator",
    "description": "Build a responsive CSS Grid visually: set tracks, gap, flow and item alignment, optionally make one card span multiple cells, then copy the CSS. The preview uses real grid properties and runs entir...",
    "category": "SaaS & Business Killers",
    "file": "css-grid-layout-generator.html",
    "path": "cards/css-grid-layout-generator.html"
  },
  {
    "id": "css-grid-playground-title",
    "name": "css-grid-playground",
    "title": "📐 CSS Grid Playground",
    "description": "Visual CSS Grid generator. Define columns, rows, and gaps with sliders. See the result live and copy the CSS.",
    "category": "Algorithms & Computer Science",
    "file": "css-grid-playground.html",
    "path": "cards/css-grid-playground.html"
  },
  {
    "id": "css-specificity-calculator-title",
    "name": "css-specificity-calculator",
    "title": "🎯 CSS Specificity Calculator",
    "description": "Paste a selector. Counts IDs, classes/attributes/pseudo-classes, and types/pseudo-elements as (A, B, C). :not() is ignored as a class; its argument is counted. :is() / :where() / :has() take the mo...",
    "category": "Algorithms & Computer Science",
    "file": "css-specificity-calculator.html",
    "path": "cards/css-specificity-calculator.html"
  },
  {
    "id": "csv-data-studio-title",
    "name": "csv-data-studio",
    "title": "📊 CSV Data Studio",
    "description": "Paste a spreadsheet, get a clean dataset. Parses CSV/TSV, detects the delimiter, profiles every column, cleans the rows, and re-exports as JSON, SQL, Markdown, XML or HTML. Nothing is uploaded — th...",
    "category": "SaaS & Business Killers",
    "file": "csv-data-studio.html",
    "path": "cards/csv-data-studio.html"
  },
  {
    "id": "csv-json-converter-title",
    "name": "csv-json-converter",
    "title": "⇄ CSV ⇄ JSON",
    "description": "First CSV row is headers. Quoted fields and doubled quotes are honoured. JSON must be an array of objects. Conversion stays on this device.",
    "category": "Algorithms & Computer Science",
    "file": "csv-json-converter.html",
    "path": "cards/csv-json-converter.html"
  },
  {
    "id": "csv-to-json-table-converter-title",
    "name": "csv-to-json-table-converter",
    "title": "📊 CSV ⇄ JSON ⇄ Markdown Table Converter",
    "description": "Paste CSV, TSV or a JSON array and convert it to JSON, CSV, Markdown table, HTML table or SQL INSERT statements. Handles quoted fields, custom delimiters and header detection. Everything stays in y...",
    "category": "Algorithms & Computer Science",
    "file": "csv-to-json-table-converter.html",
    "path": "cards/csv-to-json-table-converter.html"
  },
  {
    "id": "csv-to-json-title",
    "name": "csv-to-json",
    "title": "📊 CSV ↔ JSON Converter",
    "description": "Convert CSV data to JSON and back. Supports custom delimiters, headers, and nested objects.",
    "category": "Algorithms & Computer Science",
    "file": "csv-to-json.html",
    "path": "cards/csv-to-json.html"
  },
  {
    "id": "cubic-bezier-easing-preview-title",
    "name": "cubic-bezier-easing-preview",
    "title": "〰️ Cubic Bézier Easing",
    "description": "CSS transition-timing-function: cubic-bezier(x1, y1, x2, y2). x is time (0–1), y is progress (can overshoot). Copy the declaration after you like the motion. Respects reduced-motion.",
    "category": "Algorithms & Computer Science",
    "file": "cubic-bezier-easing-preview.html",
    "path": "cards/cubic-bezier-easing-preview.html"
  },
  {
    "id": "curl-command-builder-title",
    "name": "curl-command-builder",
    "title": "🖥️ cURL Command Builder",
    "description": "Assemble a safe-to-copy cURL command from a URL, method, headers and optional request body. It quotes shell values correctly and never sends the request itself, so you can prepare API calls private...",
    "category": "SaaS & Business Killers",
    "file": "curl-command-builder.html",
    "path": "cards/curl-command-builder.html"
  },
  {
    "id": "curling-score-calculator-title",
    "name": "curling-score-calculator",
    "title": "🥌 Curling Score Calculator",
    "description": "In each end, the team with the stone closest to the button scores one point for every stone nearer than the opposition's best. Enter each end and this keeps the running score to the last stone.",
    "category": "Sports",
    "file": "curling-score-calculator.html",
    "path": "cards/curling-score-calculator.html"
  },
  {
    "id": "currency-title",
    "name": "currency",
    "title": "💱 Currency Converter",
    "description": "Convert between 150+ currencies with live exchange rates. Using ExchangeRate-API with fallback to local data[citation:5][citation:8].",
    "category": "Finance & Money",
    "file": "currency.html",
    "path": "cards/currency.html"
  },
  {
    "id": "cv-builder-title",
    "name": "cv-builder",
    "title": "📄 Professional CV Builder",
    "description": "PROFESSIONAL CV CREATOR - Build ATS-optimized CVs with multiple templates, real-time preview, and export options. Used by career coaches worldwide.",
    "category": "Productivity & Lifestyle",
    "file": "cv-builder.html",
    "path": "cards/cv-builder.html"
  },
  {
    "id": "cycling-power-speed-calculator-title",
    "name": "cycling-power-speed-calculator",
    "title": "🚴 Cycling Power & Speed Calculator",
    "description": "How many watts to hold 40 km/h up a 4% climb? Or what speed does your FTP actually buy you? This models the three forces a rider fights — rolling resistance, air drag and gravity — and splits your ...",
    "category": "Sports",
    "file": "cycling-power-speed-calculator.html",
    "path": "cards/cycling-power-speed-calculator.html"
  },
  {
    "id": "cymatic-sound-sculpture-3d-title",
    "name": "cymatic-sound-sculpture-3d",
    "title": "🔉 3D Cymatic Sound Sculpture",
    "description": "Acoustic resonance installation. Granular silica particles migrate across a vibrating resonant Chladni plate into standing wave geometric nodal lines.",
    "category": "Science & Engineering",
    "file": "cymatic-sound-sculpture-3d.html",
    "path": "cards/cymatic-sound-sculpture-3d.html"
  },
  {
    "id": "cymatics-chladni-plate-title",
    "name": "cymatics-chladni-plate",
    "title": "📐 Chladni Cymatics Plate",
    "description": "Explore Ernst Chladni's 1787 acoustic nodal resonance figures. Observe sand grains scatter away from high-amplitude vibrating antinodes and crystallize into intricate geometric standing wave geomet...",
    "category": "Science & Engineering",
    "file": "cymatics-chladni-plate.html",
    "path": "cards/cymatics-chladni-plate.html"
  },
  {
    "id": "daily-curiosity-fact-deck-title",
    "name": "daily-curiosity-fact-deck",
    "title": "✨ Curiosity Fact Deck",
    "description": "48 verified fascinating facts across space, nature, history, the body, Earth and technology — with a fact of the day, favourites and a quiz mode that turns trivia into knowledge.",
    "category": "Productivity & Lifestyle",
    "file": "daily-curiosity-fact-deck.html",
    "path": "cards/daily-curiosity-fact-deck.html"
  },
  {
    "id": "damp-diagnostic-title",
    "name": "damp-diagnostic",
    "title": "💧 Damp & Mould Diagnostic (UK homes)",
    "description": "Answer a few questions about the damp patches, mould and smells in your home and get the most likely cause — condensation, penetrating damp, rising damp or a leak — with the practical fixes and whe...",
    "category": "Home & DIY",
    "file": "damp-diagnostic.html",
    "path": "cards/damp-diagnostic.html"
  },
  {
    "id": "damped-harmonic-oscillator-title",
    "name": "damped-harmonic-oscillator",
    "title": "⚡ Damped Oscillator Simulator",
    "description": "Analyze classical mass-spring-damper dynamics ($m\\ddot{x} + c\\dot{x} + kx = F_0\\cos\\omega t$). Inspect damping ratios ($\\zeta$), Q-factor resonance peaks, phase lag, and transient vs steady-state r...",
    "category": "Science & Engineering",
    "file": "damped-harmonic-oscillator.html",
    "path": "cards/damped-harmonic-oscillator.html"
  },
  {
    "id": "dark-sky-quality-planner-title",
    "name": "dark-sky-quality-planner",
    "title": "🌌 Dark Sky Quality Planner",
    "description": "Turn a Sky Quality Meter reading, a Bortle class or a naked-eye limiting magnitude into the others, and see what each sky condition is worth for deep-sky work. Useful for choosing a site before you...",
    "category": "Astronomy & Space",
    "file": "dark-sky-quality-planner.html",
    "path": "cards/dark-sky-quality-planner.html"
  },
  {
    "id": "darts-average-and-leg-tracker-title",
    "name": "darts-average-and-leg-tracker",
    "title": "🎯 Darts 501 Average & Leg Tracker",
    "description": "Log each visit of three darts and watch your three-dart average climb. Handles the bust rules for you — scoring more than you have left, or leaving yourself on 1 — and tracks legs won across a sess...",
    "category": "Sports",
    "file": "darts-average-and-leg-tracker.html",
    "path": "cards/darts-average-and-leg-tracker.html"
  },
  {
    "id": "darts-checkout-calculator-title",
    "name": "darts-checkout-calculator",
    "title": "🎯 Darts Checkout Calculator",
    "description": "Stood at the oche wondering how to finish? Type the score you have left and get the standard two- or three-dart checkout. Includes the full 2–170 checkout chart and a practice mode that hides the a...",
    "category": "Sports",
    "file": "darts-checkout-calculator.html",
    "path": "cards/darts-checkout-calculator.html"
  },
  {
    "id": "datecalc-title",
    "name": "datecalc",
    "title": "📅 Date Calculator",
    "description": "Calculate date differences, add/subtract days, and discover interesting date facts instantly.",
    "category": "Finance & Money",
    "file": "datecalc.html",
    "path": "cards/datecalc.html"
  },
  {
    "id": "daylight-room-simulator-title",
    "name": "daylight-room-simulator",
    "title": "☀️ The Daylight Lab",
    "description": "Watch sunlight enter a room and cast shadows as the sun moves across the sky. See how window orientation, room depth, and time of year affect daylight levels. The sun path diagram shows the sun's a...",
    "category": "Museum & Collection",
    "file": "daylight-room-simulator.html",
    "path": "cards/daylight-room-simulator.html"
  },
  {
    "id": "daylight-twilight-atlas-title",
    "name": "daylight-twilight-atlas",
    "title": "🌞 Daylight & Twilight Atlas",
    "description": "A whole year of light for any point on Earth, computed offline with the NOAA solar equations: sunrise, sunset, solar noon, the three twilights, golden hour, the compass bearing the sun rises on, ho...",
    "category": "Astronomy & Space",
    "file": "daylight-twilight-atlas.html",
    "path": "cards/daylight-twilight-atlas.html"
  },
  {
    "id": "debtpayoff-title",
    "name": "debtpayoff",
    "title": "💰 Debt Payoff Calculator",
    "description": "Calculate how long it will take to become debt-free and save money with different payoff strategies.",
    "category": "Finance & Money",
    "file": "debtpayoff.html",
    "path": "cards/debtpayoff.html"
  },
  {
    "id": "decision-matrix-weighted-scorer-title",
    "name": "decision-matrix-weighted-scorer",
    "title": "⚖️ Decision Matrix Scorer",
    "description": "Evaluate complex career, business, or lifestyle choices using weighted multi-criteria scoring. Removes emotional bias and highlights the winning tradeoff.",
    "category": "Productivity & Lifestyle",
    "file": "decision-matrix-weighted-scorer.html",
    "path": "cards/decision-matrix-weighted-scorer.html"
  },
  {
    "id": "deck-joist-span-calculator-title",
    "name": "deck-joist-span-calculator",
    "title": "🪵 Deck Joist Span & Footing Calculator",
    "description": "Check how far a joist can safely span: pick the lumber size, spacing, wood type and load, and get the maximum span plus the beam and post spacing to match.",
    "category": "Home & DIY",
    "file": "deck-joist-span-calculator.html",
    "path": "cards/deck-joist-span-calculator.html"
  },
  {
    "id": "decking-calculator-title",
    "name": "decking-calculator",
    "title": "🪵 Decking Calculator",
    "description": "Calculate boards, joists, posts, screws, and total cost for a timber decking project. Works for softwood, hardwood, and composite decking.",
    "category": "Home & DIY",
    "file": "decking-calculator.html",
    "path": "cards/decking-calculator.html"
  },
  {
    "id": "deep-sky-exposure-planner-title",
    "name": "deep-sky-exposure-planner",
    "title": "📸 Deep Sky Exposure Planner",
    "description": "How long a single subframe needs to be before the target signal clears the read and sky noise, and how many of them you need to stack. Includes the f-ratio squared penalty that makes fast scopes so...",
    "category": "Astronomy & Space",
    "file": "deep-sky-exposure-planner.html",
    "path": "cards/deep-sky-exposure-planner.html"
  },
  {
    "id": "deep-time-museum-title",
    "name": "deep-time-museum",
    "title": "🏛️ Deep Time Museum",
    "description": "Walk 4.6 billion years of Earth's story in one scroll — Hadean to Holocene, an era per hall, with an Earth-in-one-day clock, jump-chips and a catalogue-numbered plaque for every exhibit...",
    "category": "Museum & Collection",
    "file": "deep-time-museum.html",
    "path": "cards/deep-time-museum.html"
  },
  {
    "id": "delay-time-bpm-calculator-title",
    "name": "delay-time-bpm-calculator",
    "title": "🎛️ Delay Time BPM Calculator",
    "description": "Convert tempo to delay, reverb pre-delay and LFO times. Note length in milliseconds = 240,000 ÷ BPM ÷ denominator (crotchet = 4). Dotted is × 1.5; triplet is × ⅔.",
    "category": "Music & Audio",
    "file": "delay-time-bpm-calculator.html",
    "path": "cards/delay-time-bpm-calculator.html"
  },
  {
    "id": "desktop-toy-bouncy-balls-title",
    "name": "desktop-toy-bouncy-balls",
    "title": "🏀 Bouncy Ball Box",
    "description": "A box full of bouncy balls — shake, tilt, add gravity wells, and watch the chaos unfold",
    "category": "Interactive Art & Living Worlds",
    "file": "desktop-toy-bouncy-balls.html",
    "path": "cards/desktop-toy-bouncy-balls.html"
  },
  {
    "id": "desktop-toy-bubble-wrap-title",
    "name": "desktop-toy-bubble-wrap",
    "title": "🫧 Bubble Wrap Popper",
    "description": "Satisfying bubble wrap popping — click to pop, hold to drag-pop entire rows, shake to reset",
    "category": "Interactive Art & Living Worlds",
    "file": "desktop-toy-bubble-wrap.html",
    "path": "cards/desktop-toy-bubble-wrap.html"
  },
  {
    "id": "desktop-toy-catapult-title",
    "name": "desktop-toy-catapult",
    "title": "🏹 Catapult Simulator",
    "description": "Build a medieval trebuchet, load projectiles, set the counterweight, and launch!",
    "category": "Interactive Art & Living Worlds",
    "file": "desktop-toy-catapult.html",
    "path": "cards/desktop-toy-catapult.html"
  },
  {
    "id": "desktop-toy-dominoes-title",
    "name": "desktop-toy-dominoes",
    "title": "🀄 Domino Chain Reaction",
    "description": "Place dominoes in a line, tap the first one, and watch the satisfying chain reaction cascade",
    "category": "Interactive Art & Living Worlds",
    "file": "desktop-toy-dominoes.html",
    "path": "cards/desktop-toy-dominoes.html"
  },
  {
    "id": "desktop-toy-drinking-bird-title",
    "name": "desktop-toy-drinking-bird",
    "title": "🐦 Drinking Bird",
    "description": "The classic heat-engine desk toy — a bird that perpetually dips its beak into water using thermodynamics",
    "category": "Interactive Art & Living Worlds",
    "file": "desktop-toy-drinking-bird.html",
    "path": "cards/desktop-toy-drinking-bird.html"
  },
  {
    "id": "desktop-toy-fidget-spinner-title",
    "name": "desktop-toy-fidget-spinner",
    "title": "🌀 Fidget Spinner",
    "description": "Spin a fidget spinner with realistic angular momentum — flick to spin, hold to accelerate, watch it slow down",
    "category": "Interactive Art & Living Worlds",
    "file": "desktop-toy-fidget-spinner.html",
    "path": "cards/desktop-toy-fidget-spinner.html"
  },
  {
    "id": "desktop-toy-lava-lamp-title",
    "name": "desktop-toy-lava-lamp",
    "title": "🫧 Lava Lamp",
    "description": "Mesmerizing blob physics — watch wax rise, split, merge, and fall in a heated glass vessel",
    "category": "Interactive Art & Living Worlds",
    "file": "desktop-toy-lava-lamp.html",
    "path": "cards/desktop-toy-lava-lamp.html"
  },
  {
    "id": "desktop-toy-marble-run-title",
    "name": "desktop-toy-marble-run",
    "title": "🎱 Marble Run Builder",
    "description": "Place ramps and bumpers, then release marbles and watch them roll with real physics",
    "category": "Interactive Art & Living Worlds",
    "file": "desktop-toy-marble-run.html",
    "path": "cards/desktop-toy-marble-run.html"
  },
  {
    "id": "desktop-toy-rope-physics-title",
    "name": "desktop-toy-rope-physics",
    "title": "🪢 Rope Physics",
    "description": "Drag, swing, and wrap a realistic rope with verlet integration — pin ends, cut segments, add weights",
    "category": "Interactive Art & Living Worlds",
    "file": "desktop-toy-rope-physics.html",
    "path": "cards/desktop-toy-rope-physics.html"
  },
  {
    "id": "desktop-toy-sand-hourglass-title",
    "name": "desktop-toy-sand-hourglass",
    "title": "⏳ Sand Hourglass",
    "description": "Granular physics — watch thousands of sand grains flow, pile, and avalanche through a narrow neck",
    "category": "Interactive Art & Living Worlds",
    "file": "desktop-toy-sand-hourglass.html",
    "path": "cards/desktop-toy-sand-hourglass.html"
  },
  {
    "id": "desktop-toy-slinky-title",
    "name": "desktop-toy-slinky",
    "title": "Slinky Physics",
    "description": "Watch a spring slinky walk downstairs with realistic coil physics — grab it, stretch it, let it go",
    "category": "Interactive Art & Living Worlds",
    "file": "desktop-toy-slinky.html",
    "path": "cards/desktop-toy-slinky.html"
  },
  {
    "id": "desktop-toy-wave-machine-title",
    "name": "desktop-toy-wave-machine",
    "title": "〰️ Wave Machine",
    "description": "A chain of coupled pendulums — drag to create waves, watch interference patterns, and explore resonance",
    "category": "Interactive Art & Living Worlds",
    "file": "desktop-toy-wave-machine.html",
    "path": "cards/desktop-toy-wave-machine.html"
  },
  {
    "id": "dew-point-calculator-title",
    "name": "dew-point-calculator",
    "title": "💧 Dew Point Calculator",
    "description": "Magnus formula dew point from air temperature and relative humidity. Condensation risk on a surface is when the surface is at or below this dew point. Not a weather forecast.",
    "category": "Science & Engineering",
    "file": "dew-point-calculator.html",
    "path": "cards/dew-point-calculator.html"
  },
  {
    "id": "dewey-decimal-classifier-title",
    "name": "dewey-decimal-classifier",
    "title": "📚 The Dewey Stacks",
    "description": "Melvil Dewey, 1876: knowledge in ten main classes, each split by tens. Museums and small libraries still live by it. Search a word or tap a hall. This is the public summary, not a licensed DDC sche...",
    "category": "Museum & Collection",
    "file": "dewey-decimal-classifier.html",
    "path": "cards/dewey-decimal-classifier.html"
  },
  {
    "id": "dice-and-coin-roller-title",
    "name": "dice-and-coin-roller",
    "title": "🎲 Dice & Coin Roller",
    "description": "Roll virtual dice from d4 to d100, flip coins, pick random numbers or names — with totals, history and rolls.",
    "category": "MrProphecy Arcade",
    "file": "dice-and-coin-roller.html",
    "path": "cards/dice-and-coin-roller.html"
  },
  {
    "id": "diceware-passphrase-generator-title",
    "name": "diceware-passphrase-generator",
    "title": "🎲 Diceware Passphrase",
    "description": "Six words from a 256-word list, picked with crypto.getRandomValues (~48 bits). Not the official 7,776-word EFF list — treat this as a strong memorable password, then store it in a manager. Generate...",
    "category": "Algorithms & Computer Science",
    "file": "diceware-passphrase-generator.html",
    "path": "cards/diceware-passphrase-generator.html"
  },
  {
    "id": "differential-equations-title",
    "name": "differential-equations",
    "title": "🧮 AI Differential Equations Solver",
    "description": "WORLD'S FIRST interactive DE solver with step-by-step explanations, visual graphs, and real-world applications. Used by universities worldwide!",
    "category": "Finance & Money",
    "file": "differential-equations.html",
    "path": "cards/differential-equations.html"
  },
  {
    "id": "difficult-conversation-scripter-title",
    "name": "difficult-conversation-scripter",
    "title": "💬 Difficult Conversation Scripter",
    "description": "Builds you the words for a conversation you have been putting off. Nothing is sent anywhere — this works offline and nothing you type leaves your device.",
    "category": "Wellbeing & Community",
    "file": "difficult-conversation-scripter.html",
    "path": "cards/difficult-conversation-scripter.html"
  },
  {
    "id": "diffraction-grating-laser-spectrometer-title",
    "name": "diffraction-grating-laser-spectrometer",
    "title": "🌈 Holographic Laser Spectrograph",
    "description": "Optical spectrometer bench. High-density holographic diffraction grating disperses atomic gas emission into discrete quantum spectral fingerprints.",
    "category": "Science & Engineering",
    "file": "diffraction-grating-laser-spectrometer.html",
    "path": "cards/diffraction-grating-laser-spectrometer.html"
  },
  {
    "id": "dimensional-weight-shipping-calculator-title",
    "name": "dimensional-weight-shipping-calculator",
    "title": "📦 Dimensional Weight Calculator",
    "description": "Carriers bill the higher of actual weight and volumetric (dimensional) weight. Enter the box and compare IATA /6000, DHL·FedEx /5000 and US domestic /139. Not a postage quote.",
    "category": "Productivity & Lifestyle",
    "file": "dimensional-weight-shipping-calculator.html",
    "path": "cards/dimensional-weight-shipping-calculator.html"
  },
  {
    "id": "dinosaur-scale-hall-title",
    "name": "dinosaur-scale-hall",
    "title": "🦕 The Scale Hall",
    "description": "Lengths and masses as the casts in the hall give them — mid-range figures from the current literature, not movie posters. Enter your height; the gold line is you, standing at the snout.",
    "category": "Museum & Collection",
    "file": "dinosaur-scale-hall.html",
    "path": "cards/dinosaur-scale-hall.html"
  },
  {
    "id": "discount-title",
    "name": "discount",
    "title": "Discount Calculator",
    "description": "Calculate final prices after discounts and taxes. Compare multiple deals and save your calculations.",
    "category": "Finance & Money",
    "file": "discount.html",
    "path": "cards/discount.html"
  },
  {
    "id": "discrete-math-title",
    "name": "discrete-math",
    "title": "🧮 Discrete Math Toolkit",
    "description": "WORKING CALCULATOR for Computer Science & Mathematics. Real calculations for set theory, combinatorics, and logic. Everything works instantly!",
    "category": "Mathematics",
    "file": "discrete-math.html",
    "path": "cards/discrete-math.html"
  },
  {
    "id": "dividend-yield-calculator-title",
    "name": "dividend-yield-calculator",
    "title": "📈 Dividend Yield Calculator",
    "description": "Trailing yield = annual dividends per share ÷ price. Forward yield uses the next expected year. Cover = EPS ÷ DPS. This is a ratio, not investment advice, and ignores tax wrappers.",
    "category": "Finance & Money",
    "file": "dividend-yield-calculator.html",
    "path": "cards/dividend-yield-calculator.html"
  },
  {
    "id": "diving-score-calculator-title",
    "name": "diving-score-calculator",
    "title": "🤸 Diving Score Calculator",
    "description": "Score a dive the way the judges do: enter the judges' marks and the degree of difficulty, and this drops the outliers and applies the official formula to give the dive its total.",
    "category": "Sports",
    "file": "diving-score-calculator.html",
    "path": "cards/diving-score-calculator.html"
  },
  {
    "id": "dna-helix-3d-builder-title",
    "name": "dna-helix-3d-builder",
    "title": "🧬 DNA Helix 3D Builder",
    "description": "Type any DNA sequence and watch it become a spinning double helix — with correct A‑T / G‑C pairing, hydrogen bonds, live GC content, mRNA transcription and protein translation. Includes a mutation ...",
    "category": "Science & Engineering",
    "file": "dna-helix-3d-builder.html",
    "path": "cards/dna-helix-3d-builder.html"
  },
  {
    "id": "dog-calorie-portion-calculator-title",
    "name": "dog-calorie-portion-calculator",
    "title": "🥩 Canine Daily Calorie Portioner",
    "description": "WSAVA metabolic energy calculator. Formulates exact Resting Energy Requirements (RER) and daily food cup portions to maintain ideal body condition.",
    "category": "Dogs & Canine Care",
    "file": "dog-calorie-portion-calculator.html",
    "path": "cards/dog-calorie-portion-calculator.html"
  },
  {
    "id": "dog-chocolate-toxicity-calc-title",
    "name": "dog-chocolate-toxicity-calc",
    "title": "🍫 Dog Chocolate Toxicity Calc",
    "description": "Emergency veterinary theobromine toxicity calculator. Computes methylxanthine dose (mg/kg) to determine risk of cardiac arrhythmia, vomiting, and seizures.",
    "category": "Dogs & Canine Care",
    "file": "dog-chocolate-toxicity-calc.html",
    "path": "cards/dog-chocolate-toxicity-calc.html"
  },
  {
    "id": "dog-clicker-trainer-cadence-title",
    "name": "dog-clicker-trainer-cadence",
    "title": "🎯 Dog Clicker Trainer & Sound",
    "description": "Operant conditioning event marker. Features synthesized metallic clicker audio and a reaction-time latency game to calibrate your 0.8-second reward marking window.",
    "category": "Dogs & Canine Care",
    "file": "dog-clicker-trainer-cadence.html",
    "path": "cards/dog-clicker-trainer-cadence.html"
  },
  {
    "id": "dog-crate-sizing-den-blueprint-title",
    "name": "dog-crate-sizing-den-blueprint",
    "title": "🏠 Dog Crate Sizing & Den Guide",
    "description": "Orthopedic crate sizing & housebreaking den blueprint. Computes exact crate length, height, and maximum continuous confinement hours by age.",
    "category": "Dogs & Canine Care",
    "file": "dog-crate-sizing-den-blueprint.html",
    "path": "cards/dog-crate-sizing-den-blueprint.html"
  },
  {
    "id": "dog-daily-walk-exercise-calc-title",
    "name": "dog-daily-walk-exercise-calc",
    "title": "🦮 Dog Daily Walk & Activity Calc",
    "description": "Canine exercise prescription engine. Formulates daily cardio walking duration, growth-plate puppy limits (5 min/month rule), and sniffari mental enrichment.",
    "category": "Dogs & Canine Care",
    "file": "dog-daily-walk-exercise-calc.html",
    "path": "cards/dog-daily-walk-exercise-calc.html"
  },
  {
    "id": "dog-dehydration-vital-checker-title",
    "name": "dog-dehydration-vital-checker",
    "title": "🩺 Dog Vital Signs & Hydration",
    "description": "Clinical canine triage assessment. Evaluate skin turgor snapback, gum capillary refill time (CRT), normal body temperatures, and resting respiratory rates.",
    "category": "Dogs & Canine Care",
    "file": "dog-dehydration-vital-checker.html",
    "path": "cards/dog-dehydration-vital-checker.html"
  },
  {
    "id": "dog-human-age-epigenetic-calc-title",
    "name": "dog-human-age-epigenetic-calc",
    "title": "🐕 Dog Human Years Age Clock",
    "description": "UCSD School of Medicine DNA methylation epigenetic calculator (Wang et al., Cell Systems). Replaces the debunked 7-year myth with cellular age biology.",
    "category": "Dogs & Canine Care",
    "file": "dog-human-age-epigenetic-calc.html",
    "path": "cards/dog-human-age-epigenetic-calc.html"
  },
  {
    "id": "dog-photo-viewer-title",
    "name": "dog-photo-viewer",
    "title": "🐕 Dog Photo Viewer",
    "description": "COMPLETE DOG VIEWER - Browse thousands of dog photos with breed information, favorites, and infinite scrolling. Multiple API sources for maximum reliability.",
    "category": "Productivity & Lifestyle",
    "file": "dog-photo-viewer.html",
    "path": "cards/dog-photo-viewer.html"
  },
  {
    "id": "dog-safe-toxic-food-checker-title",
    "name": "dog-safe-toxic-food-checker",
    "title": "🥩 Dog Food Safety & Toxicity Key",
    "description": "Emergency canine food safety encyclopedia. Search common household foods to identify lethal toxicities (Xylitol, grapes, alliums) versus safe nutrient-dense superfoods.",
    "category": "Dogs & Canine Care",
    "file": "dog-safe-toxic-food-checker.html",
    "path": "cards/dog-safe-toxic-food-checker.html"
  },
  {
    "id": "dog-ultrasonic-whistle-trainer-title",
    "name": "dog-ultrasonic-whistle-trainer",
    "title": "📯 Dog Ultrasonic Whistle Lab",
    "description": "High-frequency acoustic trainer (14,000 Hz to 22,000 Hz). Capitalizes on canine ultrasonic hearing up to 45 kHz for long-distance park recalls and focus interrupts.",
    "category": "Dogs & Canine Care",
    "file": "dog-ultrasonic-whistle-trainer.html",
    "path": "cards/dog-ultrasonic-whistle-trainer.html"
  },
  {
    "id": "doppler-effect-simulator-title",
    "name": "doppler-effect-simulator",
    "title": "🔊 Doppler Effect Simulator",
    "description": "Simulate frequency shifts and wavefront compression for acoustic sound waves and relativistic light redshift ($z$). Features real-time wavefront propagation canvas and Web Audio tone simulation.",
    "category": "Science & Engineering",
    "file": "doppler-effect-simulator.html",
    "path": "cards/doppler-effect-simulator.html"
  },
  {
    "id": "double-pendulum-chaos-title",
    "name": "double-pendulum-chaos",
    "title": "🌀 Double Pendulum Chaos",
    "description": "Simulate non-linear Hamiltonian chaos via Lagrangian mechanics solved with 4th-Order Runge-Kutta (RK4). Track sensitive dependence on initial conditions (Butterfly Effect) with an overlaid $0.001$ ...",
    "category": "Science & Engineering",
    "file": "double-pendulum-chaos.html",
    "path": "cards/double-pendulum-chaos.html"
  },
  {
    "id": "double-slit-quantum-eraser-title",
    "name": "double-slit-quantum-eraser",
    "title": "🔬 Quantum Eraser & Double Slit",
    "description": "Quantum optics delayed-choice experiment. Observe wave interference, wavefunction collapse via which-way detectors, and quantum erasure recovery.",
    "category": "Science & Engineering",
    "file": "double-slit-quantum-eraser.html",
    "path": "cards/double-slit-quantum-eraser.html"
  },
  {
    "id": "downlight-spacing-calculator-title",
    "name": "downlight-spacing-calculator",
    "title": "💡 Downlight Spacing Calculator",
    "description": "A common rule is spacing ≈ 0.5–0.75 × ceiling height, with the first lamp about half that from the wall. Check beam angle and joists — this is a layout sketch, not a lighting design.",
    "category": "Home & DIY",
    "file": "downlight-spacing-calculator.html",
    "path": "cards/downlight-spacing-calculator.html"
  },
  {
    "id": "download-time-calculator-title",
    "name": "download-time-calculator",
    "title": "⬇️ Download Time Calculator",
    "description": "Time = file size × 8 / bitrate. ISPs advertise megabits (Mb/s), files are megabytes (MB). Real transfers are slower than the headline speed because of protocol overhead and Wi-Fi.",
    "category": "Algorithms & Computer Science",
    "file": "download-time-calculator.html",
    "path": "cards/download-time-calculator.html"
  },
  {
    "id": "dream-sign-frequency-matrix-title",
    "name": "dream-sign-frequency-matrix",
    "title": "📓 Lucid Dream Sign Analyzer",
    "description": "Identify personal recurring anomalies across your dreams (LaBerge 4-Category taxonomy). Recognizing your frequent dream signs is the #1 trigger for spontaneous lucidity.",
    "category": "Lucid Dreaming & Sleep",
    "file": "dream-sign-frequency-matrix.html",
    "path": "cards/dream-sign-frequency-matrix.html"
  },
  {
    "id": "driving-emergency-survival-guide-title",
    "name": "driving-emergency-survival-guide",
    "title": "🚗 Driving Emergency Survival Guide",
    "description": "Almost every driving emergency has one instinctive response that makes it worse and one trained response that fixes it. Pick the situation. You get the correct order of actions, the specific thing ...",
    "category": "Survival & Emergency Readiness",
    "file": "driving-emergency-survival-guide.html",
    "path": "cards/driving-emergency-survival-guide.html"
  },
  {
    "id": "drywall-calculator-title",
    "name": "drywall-calculator",
    "title": "🧱 Drywall (Plasterboard) Calculator",
    "description": "Order the right amount of board: enter the wall and ceiling area, pick a sheet size and wastage, and get the sheet count plus the joint compound, tape and screws to finish it.",
    "category": "Home & DIY",
    "file": "drywall-calculator.html",
    "path": "cards/drywall-calculator.html"
  },
  {
    "id": "duplicate-line-remover-sorter-title",
    "name": "duplicate-line-remover-sorter",
    "title": "🧹 Duplicate Line Remover",
    "description": "Paste a list: drop duplicate lines, sort A→Z or Z→A, trim spaces, ignore case. Stays in this browser — mailing lists and log dumps never leave the device.",
    "category": "Algorithms & Computer Science",
    "file": "duplicate-line-remover-sorter.html",
    "path": "cards/duplicate-line-remover-sorter.html"
  },
  {
    "id": "ear-trainer-title",
    "name": "ear-trainer",
    "title": "🎵 Ear Trainer",
    "description": "Practice recognizing musical intervals with visual guides. ⚠️ For educational purposes — always verify with professional resources.",
    "category": "Music & Audio",
    "file": "ear-trainer.html",
    "path": "cards/ear-trainer.html"
  },
  {
    "id": "earth-tide-clock-title",
    "name": "earth-tide-clock",
    "title": "🌙 Earth Tide Clock",
    "description": "Two tidal bulges, not one. The Moon (and a weaker Sun) stretch Earth into a prolate spheroid; a port rotates through both bulges and sees two highs a day. Align Moon and Sun for spring tide; put th...",
    "category": "Astronomy & Space",
    "file": "earth-tide-clock.html",
    "path": "cards/earth-tide-clock.html"
  },
  {
    "id": "earthing-calculator-title",
    "name": "earthing-calculator",
    "title": "⚡ Earthing Conductor Calculator",
    "description": "For qualified electricians. Always verify with local regulations and manufacturer specifications.",
    "category": "Science & Engineering",
    "file": "earthing-calculator.html",
    "path": "cards/earthing-calculator.html"
  },
  {
    "id": "earthquake-seismograph-lab-title",
    "name": "earthquake-seismograph-lab",
    "title": "🫨 Earthquake Seismograph Lab",
    "description": "Trigger a fault rupture and watch P, S and surface waves race outward — then read the synthetic seismogram: S−P time lag gives the distance, amplitude gives the magnitude, and seismic attenuation b...",
    "category": "Interactive Art & Living Worlds",
    "file": "earthquake-seismograph-lab.html",
    "path": "cards/earthquake-seismograph-lab.html"
  },
  {
    "id": "echo-pond-water-cymatics-soundscape-title",
    "name": "echo-pond-water-cymatics-soundscape",
    "title": "🌊 EchoPond Cymatics",
    "description": "A communal fluid-dynamics sanctuary. Cast water drops into a resonant pond. Wave ripples interfere via the physical wave equation, triggering soothing pentatonic water chimes when constructive wave...",
    "category": "Interactive Art & Living Worlds",
    "file": "echo-pond-water-cymatics-soundscape.html",
    "path": "cards/echo-pond-water-cymatics-soundscape.html"
  },
  {
    "id": "eco-footprint-accelerator-title",
    "name": "eco-footprint-accelerator",
    "title": "🌍 Eco Footprint Calculator",
    "description": "Move past vague carbon guilt. PlanetPositive pinpoints the exact 80/20 high-leverage lifestyle actions that slash personal emissions the fastest while saving hundreds of pounds each year.",
    "category": "Science & Engineering",
    "file": "eco-footprint-accelerator.html",
    "path": "cards/eco-footprint-accelerator.html"
  },
  {
    "id": "ecology-title",
    "name": "ecology",
    "title": "🌍 Professional Ecology Calculator",
    "description": "🔬 A comprehensive suite of ecological calculations for researchers, environmental scientists, and conservation professionals. Includes statistical analysis, biodiversity metrics, and ecosystem mod...",
    "category": "Science & Engineering",
    "file": "ecology.html",
    "path": "cards/ecology.html"
  },
  {
    "id": "edu-anatomy-title",
    "name": "edu-anatomy",
    "title": "🫀 Human Anatomy Explorer",
    "description": "Interactive body systems — click organs and systems to learn their functions, facts, and connections",
    "category": "Science & Engineering",
    "file": "edu-anatomy.html",
    "path": "cards/edu-anatomy.html"
  },
  {
    "id": "edu-constellation-map-title",
    "name": "edu-constellation-map",
    "title": "⭐ Constellation Map",
    "description": "Interactive star map — explore 30 major constellations, click stars for names and facts",
    "category": "Astronomy & Space",
    "file": "edu-constellation-map.html",
    "path": "cards/edu-constellation-map.html"
  },
  {
    "id": "edu-country-data-title",
    "name": "edu-country-data",
    "title": "🌍 Country Data Visualizer",
    "description": "Compare countries by population, area, GDP, and more — with animated bar charts and data cards",
    "category": "Science & Engineering",
    "file": "edu-country-data.html",
    "path": "cards/edu-country-data.html"
  },
  {
    "id": "edu-dna-translator-title",
    "name": "edu-dna-translator",
    "title": "🧬 DNA → Protein Translator",
    "description": "Paste a DNA or mRNA sequence and watch it get transcribed and translated into amino acids — with a visual codon table",
    "category": "Science & Engineering",
    "file": "edu-dna-translator.html",
    "path": "cards/edu-dna-translator.html"
  },
  {
    "id": "edu-math-3d-title",
    "name": "edu-math-3d",
    "title": "📐 3D Function Plotter",
    "description": "Visualize 3D mathematical surfaces — rotate, zoom, and explore equations in real time",
    "category": "Mathematics",
    "file": "edu-math-3d.html",
    "path": "cards/edu-math-3d.html"
  },
  {
    "id": "edu-music-theory-title",
    "name": "edu-music-theory",
    "title": "🎵 Music Theory Visualizer",
    "description": "Explore scales, chords, and intervals on a virtual piano — hear how they sound and see the theory behind them",
    "category": "Music & Audio",
    "file": "edu-music-theory.html",
    "path": "cards/edu-music-theory.html"
  },
  {
    "id": "edu-periodic-table-title",
    "name": "edu-periodic-table",
    "title": "⚛️ Interactive Periodic Table",
    "description": "Explore all 118 elements — click any element for detailed properties, electron configuration, and fun facts",
    "category": "Science & Engineering",
    "file": "edu-periodic-table.html",
    "path": "cards/edu-periodic-table.html"
  },
  {
    "id": "edu-rock-identifier-title",
    "name": "edu-rock-identifier",
    "title": "🪨 Rock & Mineral Identifier",
    "description": "Answer a few questions about your rock and get an identification — with visual examples and properties",
    "category": "Science & Engineering",
    "file": "edu-rock-identifier.html",
    "path": "cards/edu-rock-identifier.html"
  },
  {
    "id": "edu-solar-system-title",
    "name": "edu-solar-system",
    "title": "🪐 Solar System Explorer",
    "description": "Animated orrery of our solar system — watch planets orbit in real time, click for detailed facts",
    "category": "Astronomy & Space",
    "file": "edu-solar-system.html",
    "path": "cards/edu-solar-system.html"
  },
  {
    "id": "edu-timeline-builder-title",
    "name": "edu-timeline-builder",
    "title": "📜 Historical Timeline Builder",
    "description": "Create beautiful visual timelines — add events, see them plotted chronologically with color-coded categories",
    "category": "Science & Engineering",
    "file": "edu-timeline-builder.html",
    "path": "cards/edu-timeline-builder.html"
  },
  {
    "id": "egyptian-hieroglyph-alphabet-title",
    "name": "egyptian-hieroglyph-alphabet",
    "title": "𓂀 The Uniliteral Case",
    "description": "The twenty-four single-consonant signs every student copies first — Gardiner’s teaching alphabet. Vowels were not written. Type a name; the case sets the glyphs and the catalogue codes. This is not...",
    "category": "Museum & Collection",
    "file": "egyptian-hieroglyph-alphabet.html",
    "path": "cards/egyptian-hieroglyph-alphabet.html"
  },
  {
    "id": "electrical-standards-title",
    "name": "electrical-standards",
    "title": "📚 Electrical Standards Guide",
    "description": "📋 Copy Full Report 💾 Save as PDF // Global Electrical Standards Reference let currentRegion = 'iec'; const standardsData = { iec: { name: \"International Electrotechnical Commission (IEC)\", color:...",
    "category": "Science & Engineering",
    "file": "electrical-standards.html",
    "path": "cards/electrical-standards.html"
  },
  {
    "id": "electricity-title",
    "name": "electricity",
    "title": "⚡ Electrical Engineering Calculator",
    "description": "🔬 A comprehensive electrical engineering toolkit for professionals and students. Includes circuit analysis, power calculations, and energy conversions with real-world context.",
    "category": "Science & Engineering",
    "file": "electricity.html",
    "path": "cards/electricity.html"
  },
  {
    "id": "element-hall-title",
    "name": "element-hall",
    "title": "⚗️ The Element Hall",
    "description": "All 118 elements as numbered museum exhibits: discovery year, discoverers, name origin, category, state at room temperature — plus curator's notes on two dozen showpieces and an honest word where d...",
    "category": "Museum & Collection",
    "file": "element-hall.html",
    "path": "cards/element-hall.html"
  },
  {
    "id": "email-signature-generator-title",
    "name": "email-signature-generator",
    "title": "📧 Signature Forge",
    "description": "Build an email signature that survives Gmail, Outlook and Apple Mail, then copy it with formatting intact and paste straight into your mail client. Table-based layout, inline styles only, no script...",
    "category": "SaaS & Business Killers",
    "file": "email-signature-generator.html",
    "path": "cards/email-signature-generator.html"
  },
  {
    "id": "email-subject-line-tester-title",
    "name": "email-subject-line-tester",
    "title": "✉️ Email Subject Line Tester",
    "description": "Preview how a subject line and preheader may truncate on mobile or desktop, check length and punctuation, and get practical editing prompts. This is a transparent writing heuristic — not a delivera...",
    "category": "SaaS & Business Killers",
    "file": "email-subject-line-tester.html",
    "path": "cards/email-subject-line-tester.html"
  },
  {
    "id": "email-templates-title",
    "name": "email-templates",
    "title": "📧 Email Template Generator",
    "description": "💼 Generate perfectly crafted professional emails, LinkedIn messages, and business communications. Includes tone analysis, etiquette tips, and productivity features.",
    "category": "Writing & Language",
    "file": "email-templates.html",
    "path": "cards/email-templates.html"
  },
  {
    "id": "emergency-comms-radio-planner-title",
    "name": "emergency-comms-radio-planner",
    "title": "📡 Emergency Communications & Radio Planner",
    "description": "In every major incident the mobile network is the first thing to fail — not from damage, but from everybody calling at once. This works out what you can actually reach with, how far a handheld radi...",
    "category": "Survival & Emergency Readiness",
    "file": "emergency-comms-radio-planner.html",
    "path": "cards/emergency-comms-radio-planner.html"
  },
  {
    "id": "emoji-meaning-decoder-title",
    "name": "emoji-meaning-decoder",
    "title": "🤔 What Does That Emoji *Actually* Mean?",
    "description": "The generational emoji gap, decoded. Search or tap an emoji to see what it really means, how your boss probably reads it, and whether it's safe for the work chat. You will never send 🙏 in the grou...",
    "category": "Productivity & Lifestyle",
    "file": "emoji-meaning-decoder.html",
    "path": "cards/emoji-meaning-decoder.html"
  },
  {
    "id": "employee-true-cost-calculator-title",
    "name": "employee-true-cost-calculator",
    "title": "👥 Employee True Cost Calculator",
    "description": "Estimate the fully loaded annual and monthly cost of hiring beyond the headline salary. All calculations stay in your browser.",
    "category": "Finance & Money",
    "file": "employee-true-cost-calculator.html",
    "path": "cards/employee-true-cost-calculator.html"
  },
  {
    "id": "energy-tariff-comparator-title",
    "name": "energy-tariff-comparator",
    "title": "⚡ Energy Tariff Comparator",
    "description": "Suppliers advertise the unit rate because it is the flattering number, but the standing charge is paid every single day whether you use anything or not. This compares the real annual cost — and, mo...",
    "category": "Finance & Money",
    "file": "energy-tariff-comparator.html",
    "path": "cards/energy-tariff-comparator.html"
  },
  {
    "id": "energy-watt-exchange-title",
    "name": "energy-watt-exchange",
    "title": "⚡ The Watt Exchange",
    "description": "Energy literacy in the only currency that needs no conversion: bananas, stairs and phone charges. Decode any item, your monthly meter, and the kinetic energy of a moving car (E = ½mv²).",
    "category": "Museum & Collection",
    "file": "energy-watt-exchange.html",
    "path": "cards/energy-watt-exchange.html"
  },
  {
    "id": "energy-title",
    "name": "energy",
    "title": "⚡ Energy Consumption Calculator",
    "description": "Calculate electricity costs, carbon footprint, and savings potential for any appliance. Track your energy usage and find ways to save money!",
    "category": "Science & Engineering",
    "file": "energy.html",
    "path": "cards/energy.html"
  },
  {
    "id": "engine-displacement-converter-title",
    "name": "engine-displacement-converter",
    "title": "🛠️ Engine Displacement",
    "description": "Convert litres, cubic centimetres and cubic inches (CID). 1 L = 1,000 cc; 1 in³ = 16.387064 cm³. A “5.0” V8 is 5,000 cc ≈ 305 CID. Bore × stroke × cylinders is the geometric displacement, not power.",
    "category": "Interactive Art & Living Worlds",
    "file": "engine-displacement-converter.html",
    "path": "cards/engine-displacement-converter.html"
  },
  {
    "id": "environmental-science-title",
    "name": "environmental-science",
    "title": "🌍 Environmental Science Tools",
    "description": "Calculate environmental impacts, explore sustainability metrics, and learn fascinating facts about Earth's systems. Make informed decisions for a greener planet!",
    "category": "Science & Engineering",
    "file": "environmental-science.html",
    "path": "cards/environmental-science.html"
  },
  {
    "id": "equation-solver-title",
    "name": "equation-solver",
    "title": "📐 Equation Solver",
    "description": "Solve algebraic equations step-by-step. Supports linear, quadratic, and cubic equations. Try examples below!",
    "category": "Mathematics",
    "file": "equation-solver.html",
    "path": "cards/equation-solver.html"
  },
  {
    "id": "equatorial-coord-finder-title",
    "name": "equatorial-coord-finder",
    "title": "🧭 Equatorial Coordinate Finder",
    "description": "Convert right ascension and declination into altitude and azimuth for your latitude and local sidereal time — or go the other way. Tells you whether a target is up, where to point, and when it tran...",
    "category": "Astronomy & Space",
    "file": "equatorial-coord-finder.html",
    "path": "cards/equatorial-coord-finder.html"
  },
  {
    "id": "erosion-landscape-lab-title",
    "name": "erosion-landscape-lab",
    "title": "⛰️ Erosion & Landscape Lab",
    "description": "Sculpt a landscape and watch it move. Set rainfall, soil erodibility, vegetation cover and steepness — the runoff erodes the hills, transport by flowing water sorts/deposits the sediment downstream...",
    "category": "Interactive Art & Living Worlds",
    "file": "erosion-landscape-lab.html",
    "path": "cards/erosion-landscape-lab.html"
  },
  {
    "id": "essay-templates-title",
    "name": "essay-templates",
    "title": "📝 Essay Writing Assistant",
    "description": "Generate structured essay outlines, starter paragraphs, and writing guidance for any topic. Perfect for students, writers, and professionals!",
    "category": "Writing & Language",
    "file": "essay-templates.html",
    "path": "cards/essay-templates.html"
  },
  {
    "id": "essay-title",
    "name": "essay",
    "title": "🧭 Argument Mapper",
    "description": "Structure an essay or debate case before you write it. Lay out your thesis, the premises supporting it and the strongest objections, then score how well each one actually holds up.",
    "category": "Writing & Language",
    "file": "essay.html",
    "path": "cards/essay.html"
  },
  {
    "id": "essential-oil-dilution-calc-title",
    "name": "essential-oil-dilution-calc",
    "title": "💧 Essential Oil Dilution Calc",
    "description": "Aromatherapy dermal safety calculator (Tisserand Institute standards). Computes precise drop counts per carrier oil volume to prevent sensitization and burns.",
    "category": "Natural Remedies & Herbs",
    "file": "essential-oil-dilution-calc.html",
    "path": "cards/essential-oil-dilution-calc.html"
  },
  {
    "id": "eulers-identity-rotation-title",
    "name": "eulers-identity-rotation",
    "title": "⚡ Euler's Identity: e^{iπ} = −1",
    "description": "The \"most beautiful equation\" in one picture: eiθ is just a point rotating around a circle. Wind θ up to π and you've spun exactly half a turn — to −1. eiπ + 1 = 0.",
    "category": "Mind-Blowing Demos",
    "file": "eulers-identity-rotation.html",
    "path": "cards/eulers-identity-rotation.html"
  },
  {
    "id": "ev-charging-cost-calculator-title",
    "name": "ev-charging-cost-calculator",
    "title": "🔌 EV Charging Cost & Time",
    "description": "Estimate kWh, cost and wall-clock time to charge an electric car. Uses usable battery size, start/end state of charge, charger kW and unit rate. Peak DC rates taper — treat rapid times as optimistic.",
    "category": "Finance & Money",
    "file": "ev-charging-cost-calculator.html",
    "path": "cards/ev-charging-cost-calculator.html"
  },
  {
    "id": "evacuation-go-bag-planner-title",
    "name": "evacuation-go-bag-planner",
    "title": "🎒 Evacuation & Go-Bag Planner",
    "description": "Three different emergencies need three different bags, and most people prepare the wrong one. Build all three here, weigh them against what you can actually carry, and print a checklist. The point ...",
    "category": "Survival & Emergency Readiness",
    "file": "evacuation-go-bag-planner.html",
    "path": "cards/evacuation-go-bag-planner.html"
  },
  {
    "id": "event-title",
    "name": "event",
    "title": "📅 Event Reminder",
    "description": "Set reminders for upcoming events with notifications, priorities, and recurrence options.",
    "category": "Productivity & Lifestyle",
    "file": "event.html",
    "path": "cards/event.html"
  },
  {
    "id": "evolution-arena-3d-title",
    "name": "evolution-arena-3d",
    "title": "🧬 Evolution Arena — 3D Creature Evolution",
    "description": "Evolve 3D creatures from scratch with a real genetic algorithm. Bodies of nodes and muscles are bred alongside their neural nets, then tested on walking, jumping, climbing, sumo and bridge combat.",
    "category": "Mind-Blowing Demos",
    "file": "evolution-arena-3d.html",
    "path": "cards/evolution-arena-3d.html"
  },
  {
    "id": "evolution-walker-title",
    "name": "evolution-walker",
    "title": "Evolution AI Walker",
    "description": "Watch AI creatures evolve to walk, survive disasters, find food, and adapt! 10 terrain types, random events, food chains, achievements, and deep genetics. Creatures improve through natural selection.",
    "category": "Science & Engineering",
    "file": "evolution-walker.html",
    "path": "cards/evolution-walker.html"
  },
  {
    "id": "exam-prep-maths-title",
    "name": "exam-prep-maths",
    "title": "📚 Exam Prep - Mathematics",
    "description": "COMPLETE MATH PREP - Generate practice problems with step-by-step solutions. Track your progress across 500+ questions covering all major topics.",
    "category": "Mathematics",
    "file": "exam-prep-maths.html",
    "path": "cards/exam-prep-maths.html"
  },
  {
    "id": "exam-title",
    "name": "exam",
    "title": "🎯 Exam & Study Planner",
    "description": "📚 A comprehensive exam planning and study management system for students and professionals. Track exams, create study schedules, set goals, and manage revision.",
    "category": "Productivity & Lifestyle",
    "file": "exam.html",
    "path": "cards/exam.html"
  },
  {
    "id": "excuse-generator-title",
    "name": "excuse-generator",
    "title": "🙃 Professional Excuse Generator",
    "description": "Generate increasingly absurd excuses for any situation. From \"plausible\" to \"they'll never believe you.\"",
    "category": "Productivity & Lifestyle",
    "file": "excuse-generator.html",
    "path": "cards/excuse-generator.html"
  },
  {
    "id": "experiment-ideas-title",
    "name": "experiment-ideas",
    "title": "🔬 Science Experiment Generator",
    "description": "Generate creative, hands-on science experiment ideas for all ages. Perfect for students, teachers, and curious minds!",
    "category": "Science & Engineering",
    "file": "experiment-ideas.html",
    "path": "cards/experiment-ideas.html"
  },
  {
    "id": "exponents-title",
    "name": "exponents",
    "title": "⚡ Exponents & Roots Calculator",
    "description": "Calculate powers, roots, and exponential functions with detailed steps and visualizations. Perfect for students learning algebra and calculus.",
    "category": "Mathematics",
    "file": "exponents.html",
    "path": "cards/exponents.html"
  },
  {
    "id": "extruded-3d-text-studio-title",
    "name": "extruded-3d-text-studio",
    "title": "✏️ Extruded 3D Text Studio",
    "description": "Design chunky 3D logos: real perspective rotation (rendered slice-by-slice in software), adjustable extrusion depth, bevel light, backdrops and one-click PNG export. No WebGL, no libraries — just m...",
    "category": "Productivity & Lifestyle",
    "file": "extruded-3d-text-studio.html",
    "path": "cards/extruded-3d-text-studio.html"
  },
  {
    "id": "fabric-yardage-estimator-title",
    "name": "fabric-yardage-estimator",
    "title": "🧵 Fabric Yardage Estimator",
    "description": "Pattern envelopes quote fabric for one specific width, and most fabric is not sold in that width. This converts for the width you actually bought, then adds the three allowances people forget: a pa...",
    "category": "Productivity & Lifestyle",
    "file": "fabric-yardage-estimator.html",
    "path": "cards/fabric-yardage-estimator.html"
  },
  {
    "id": "factors-multiples-trainer-title",
    "name": "factors-multiples-trainer",
    "title": "🔢 Factors & Multiples Trainer",
    "description": "List the factors and multiples of any number, then practise finding the highest common factor, lowest common multiple and factor/multiple facts.",
    "category": "Mathematics",
    "file": "factors-multiples-trainer.html",
    "path": "cards/factors-multiples-trainer.html"
  },
  {
    "id": "faraday-waves-cymatics-fluid-title",
    "name": "faraday-waves-cymatics-fluid",
    "title": "💧 Faraday Fluid Waves",
    "description": "Simulate Michael Faraday's 1831 parametric liquid surface waves ($\\omega^2 = [gk + \\frac{\\sigma}{\\rho}k^3]\\tanh kh$). Observe subharmonic resonance ($f_{wave} = f_0/2$) and pattern transitions acro...",
    "category": "Science & Engineering",
    "file": "faraday-waves-cymatics-fluid.html",
    "path": "cards/faraday-waves-cymatics-fluid.html"
  },
  {
    "id": "favicon-svg-icon-generator-title",
    "name": "favicon-svg-icon-generator",
    "title": "🪄 Favicon & SVG Icon Generator",
    "description": "Make a sharp, lightweight vector favicon from initials or one emoji, tune its colours and shape, then download a ready-to-use SVG. It also gives you the HTML link tag and a data URI — no image uplo...",
    "category": "SaaS & Business Killers",
    "file": "favicon-svg-icon-generator.html",
    "path": "cards/favicon-svg-icon-generator.html"
  },
  {
    "id": "feet-inches-cm-height-converter-title",
    "name": "feet-inches-cm-height-converter",
    "title": "📏 Feet & Inches ⇄ cm",
    "description": "Convert height between feet+inches, centimetres and metres. Uses the international inch (exactly 25.4 mm). Edit any box — the others update.",
    "category": "Science & Engineering",
    "file": "feet-inches-cm-height-converter.html",
    "path": "cards/feet-inches-cm-height-converter.html"
  },
  {
    "id": "fence-calculator-title",
    "name": "fence-calculator",
    "title": "🏗️ Fence Calculator",
    "description": "Calculate posts, panels, gravel boards, concrete, and total cost for a garden fence. Works for panel fencing, closeboard, and picket styles.",
    "category": "Home & DIY",
    "file": "fence-calculator.html",
    "path": "cards/fence-calculator.html"
  },
  {
    "id": "fermentation-salt-brine-calc-title",
    "name": "fermentation-salt-brine-calc",
    "title": "🥬 Lacto-Fermentation Salt Calc",
    "description": "Microbiological lacto-fermentation salt formulation tool. Calculates total-mass salinity, microbial succession timelines (Leuconostoc to Lactobacillus), and target pH < 4.6.",
    "category": "Culinary & Food Science",
    "file": "fermentation-salt-brine-calc.html",
    "path": "cards/fermentation-salt-brine-calc.html"
  },
  {
    "id": "ferrofluid-spike-sculpture-title",
    "name": "ferrofluid-spike-sculpture",
    "title": "🧲 Ferrofluid Spiking Lab",
    "description": "Rosensweig normal-field magnetic instability simulator. Superparamagnetic liquid self-organizes into conical spikes balancing surface tension and magnetic stress.",
    "category": "Science & Engineering",
    "file": "ferrofluid-spike-sculpture.html",
    "path": "cards/ferrofluid-spike-sculpture.html"
  },
  {
    "id": "fiber-optic-total-internal-reflection-title",
    "name": "fiber-optic-total-internal-reflection",
    "title": "✨ Fiber Optic Light Guide Lab",
    "description": "Total internal reflection fiber optics lab. Explore critical angle guidance, acceptance cone numerical aperture (NA), and macro-bending radiation loss.",
    "category": "Science & Engineering",
    "file": "fiber-optic-total-internal-reflection.html",
    "path": "cards/fiber-optic-total-internal-reflection.html"
  },
  {
    "id": "fire-escape-smoke-safety-planner-title",
    "name": "fire-escape-smoke-safety-planner",
    "title": "🔥 Fire Escape & Smoke Safety Planner",
    "description": "Most fire deaths are not from flames — they are from smoke, at night, in homes where nobody had ever worked out a route. Answer twenty questions about your home and this builds a real escape plan, ...",
    "category": "Survival & Emergency Readiness",
    "file": "fire-escape-smoke-safety-planner.html",
    "path": "cards/fire-escape-smoke-safety-planner.html"
  },
  {
    "id": "fire-financial-independence-calc-title",
    "name": "fire-financial-independence-calc",
    "title": "🔥 FIRE Retirement Planner",
    "description": "Calculate your exact Financial Independence number, years until retirement, and compound investment growth trajectory using the 4% Safe Withdrawal Rule.",
    "category": "Finance & Money",
    "file": "fire-financial-independence-calc.html",
    "path": "cards/fire-financial-independence-calc.html"
  },
  {
    "id": "fiscal-quarter-finder-title",
    "name": "fiscal-quarter-finder",
    "title": "📊 Fiscal Quarter Finder",
    "description": "Calendar quarters, the UK tax year (6 April–5 April) and the US federal fiscal year (starts 1 October). Pick a date; see which Q you are in and when it ends.",
    "category": "Finance & Money",
    "file": "fiscal-quarter-finder.html",
    "path": "cards/fiscal-quarter-finder.html"
  },
  {
    "id": "fitnesscore-title",
    "name": "fitnesscore",
    "title": "🏃‍♂️ Fitness Score Analyzer",
    "description": "Calculate your comprehensive fitness score with detailed insights and personalized recommendations. Based on scientific health metrics and activity analysis.",
    "category": "Health & Fitness",
    "file": "fitnesscore.html",
    "path": "cards/fitnesscore.html"
  },
  {
    "id": "flash-flood-lab-title",
    "name": "flash-flood-lab",
    "title": "🌧️ Rainfall & Flash Flood Lab",
    "description": "A catchment that converts rain into a flood hydrograph. Horton infiltration soaks the soil, the rational method produces peak discharge, and a Kirpich time-of-concentration shapes the river's rise ...",
    "category": "Interactive Art & Living Worlds",
    "file": "flash-flood-lab.html",
    "path": "cards/flash-flood-lab.html"
  },
  {
    "id": "flashcards-title",
    "name": "flashcards",
    "title": "📚 Smart Flashcards",
    "description": "Create beautiful, interactive flashcards for effective studying. Supports rich text, categories, and spaced repetition.",
    "category": "Productivity & Lifestyle",
    "file": "flashcards.html",
    "path": "cards/flashcards.html"
  },
  {
    "id": "flat-pack-confidence-meter-title",
    "name": "flat-pack-confidence-meter",
    "title": "🔩 Flat-Pack Confidence Meter",
    "description": "Enter the flat-pack battlefield armed with the truth: how many pieces, which tools, who's helping, and how many drinks deep you are. It will forecast your evening with alarming accuracy.",
    "category": "Productivity & Lifestyle",
    "file": "flat-pack-confidence-meter.html",
    "path": "cards/flat-pack-confidence-meter.html"
  },
  {
    "id": "flavor-wine-pairing-matrix-title",
    "name": "flavor-wine-pairing-matrix",
    "title": "🍷 Food & Wine Pairing Matrix",
    "description": "Sommelier palate chemistry engine. Evaluates flavor interactions between tannins, fats, acids, umami, and capsaicin to recommend optimal wine varietals and serving temperatures.",
    "category": "Culinary & Food Science",
    "file": "flavor-wine-pairing-matrix.html",
    "path": "cards/flavor-wine-pairing-matrix.html"
  },
  {
    "id": "flesch-reading-ease-title",
    "name": "flesch-reading-ease",
    "title": "📖 Flesch Reading Ease",
    "description": "Score = 206.835 − 1.015×(words/sentences) − 84.6×(syllables/words). 60–70 is plain English; under 30 is academic. Syllables are guessed from vowel groups — close, not a linguist.",
    "category": "Writing & Language",
    "file": "flesch-reading-ease.html",
    "path": "cards/flesch-reading-ease.html"
  },
  {
    "id": "flight-delay-compensation-checker-title",
    "name": "flight-delay-compensation-checker",
    "title": "✈️ Flight Delay Compensation Checker",
    "description": "Delayed, cancelled or denied boarding? UK261 can entitle you to up to £520 per passenger — and claim firms take 25–40% of it for filling in a form. Check your entitlement and generate the airline l...",
    "category": "Finance & Money",
    "file": "flight-delay-compensation-checker.html",
    "path": "cards/flight-delay-compensation-checker.html"
  },
  {
    "id": "flue-draft-stove-sizing-calculator-title",
    "name": "flue-draft-stove-sizing-calculator",
    "title": "🔥 Flue Draft & Stove Sizing Calculator",
    "description": "A chimney is an engine: hot gas inside, cold air outside, and the density difference pulls the fire along. This works out how much draught your flue actually generates, how fast the gas moves, how ...",
    "category": "Science & Engineering",
    "file": "flue-draft-stove-sizing-calculator.html",
    "path": "cards/flue-draft-stove-sizing-calculator.html"
  },
  {
    "id": "fluid-reynolds-number-title",
    "name": "fluid-reynolds-number",
    "title": "🌊 Reynolds Number Simulator",
    "description": "Calculate the dimensionless Reynolds number ($\\text{Re} = \\frac{\\rho v D}{\\mu}$) for internal pipe flow and aerodynamics. Visualize laminar streamline transitions into chaotic turbulent vortices.",
    "category": "Science & Engineering",
    "file": "fluid-reynolds-number.html",
    "path": "cards/fluid-reynolds-number.html"
  },
  {
    "id": "fluid-type-scale-title",
    "name": "fluid-type-scale",
    "title": "🔠 Fluid Type Scale Generator",
    "description": "Generates a typographic scale where every size scales smoothly between two screen widths, using the CSS clamp() function — no media queries, no jump at a breakpoint, and no text that is 14px on a p...",
    "category": "Productivity & Lifestyle",
    "file": "fluid-type-scale.html",
    "path": "cards/fluid-type-scale.html"
  },
  {
    "id": "fluid-vortex-smoke-tunnel-title",
    "name": "fluid-vortex-smoke-tunnel",
    "title": "🌪️ Fluid Smoke Tunnel",
    "description": "Aerodynamic wind tunnel museum exhibit. Visualize laminar airflow, von Kármán vortex shedding, and lift/drag forces around aerodynamic obstacles.",
    "category": "Science & Engineering",
    "file": "fluid-vortex-smoke-tunnel.html",
    "path": "cards/fluid-vortex-smoke-tunnel.html"
  },
  {
    "id": "focus-title",
    "name": "focus",
    "title": "⏱️ Deep Focus Timer",
    "description": "Advanced Pomodoro timer with productivity tracking, ambient sounds, and progress visualization. Stay focused, maximize productivity!",
    "category": "Productivity & Lifestyle",
    "file": "focus.html",
    "path": "cards/focus.html"
  },
  {
    "id": "food-shelf-life-storage-vault-title",
    "name": "food-shelf-life-storage-vault",
    "title": "🧊 Food Shelf-Life & Safety",
    "description": "USDA / FDA Food Safety & Inspection Service shelf-life database. Evaluates storage windows across Pantry, Refrigerator, and Freezer, plus Danger Zone temperature limits.",
    "category": "Culinary & Food Science",
    "file": "food-shelf-life-storage-vault.html",
    "path": "cards/food-shelf-life-storage-vault.html"
  },
  {
    "id": "food-web-ecosystem-lab-title",
    "name": "food-web-ecosystem-lab",
    "title": "🕸️ Food Web & Trophic Energy Lab",
    "description": "Build a food web and see it breathe. Pick a habitat, toggle species in or out, set sunlight/rainfall and the predation rate — then run the simulation: producer growth, consumer–prey dynamics (logis...",
    "category": "Interactive Art & Living Worlds",
    "file": "food-web-ecosystem-lab.html",
    "path": "cards/food-web-ecosystem-lab.html"
  },
  {
    "id": "football-points-needed-title",
    "name": "football-points-needed",
    "title": "⚽ Football Points-Needed Calculator",
    "description": "The run-in made simple. Put in where your team stands, how many games are left, and the points you are aiming for — a title, promotion, safety mark or a rival — and see exactly what the remaining f...",
    "category": "Sports",
    "file": "football-points-needed.html",
    "path": "cards/football-points-needed.html"
  },
  {
    "id": "formula-library-title",
    "name": "formula-library",
    "title": "📚 Scientific Formula Library",
    "description": "Interactive scientific formula calculator with detailed explanations, 3D visualizations, and step-by-step solutions. Perfect for students and professionals in STEM fields.",
    "category": "Mathematics",
    "file": "formula-library.html",
    "path": "cards/formula-library.html"
  },
  {
    "id": "formula1-championship-points-title",
    "name": "formula1-championship-points",
    "title": "🏁 F1 Championship Points Calculator",
    "description": "Tally a driver's season under the current 2025 points system — 25 down to 1 for the top ten, 8 down to 1 for a sprint — and see the running total, points per round, and how it compares with a rival.",
    "category": "Sports",
    "file": "formula1-championship-points.html",
    "path": "cards/formula1-championship-points.html"
  },
  {
    "id": "foucault-pendulum-earth-spin-title",
    "name": "foucault-pendulum-earth-spin",
    "title": "🌍 Foucault Pendulum Spin",
    "description": "Léon Foucault's 1851 Paris Panthéon experiment proving Earth's diurnal rotation. The swing plane stays fixed in inertial space while Earth rotates below.",
    "category": "Science & Engineering",
    "file": "foucault-pendulum-earth-spin.html",
    "path": "cards/foucault-pendulum-earth-spin.html"
  },
  {
    "id": "four-bar-linkage-kinematics-title",
    "name": "four-bar-linkage-kinematics",
    "title": "⚙️ Four-Bar Mechanism Lab",
    "description": "Synthesize planar four-bar kinematic mechanisms. Classify via Grashof's Theorem ($s + l \\le p + q$), trace coupler curves (Chebyshev, Watt, Hoeken), and analyze transmission angles.",
    "category": "Science & Engineering",
    "file": "four-bar-linkage-kinematics.html",
    "path": "cards/four-bar-linkage-kinematics.html"
  },
  {
    "id": "fourier-series-synthesizer-title",
    "name": "fourier-series-synthesizer",
    "title": "🌊 Fourier Series Synthesizer",
    "description": "Any repeating shape — a square wave, a sawtooth, your favourite tune — is just spinning circles added together. Watch a few sine waves stack into a crisp corner, then add more and see it sharpen.",
    "category": "Mind-Blowing Demos",
    "file": "fourier-series-synthesizer.html",
    "path": "cards/fourier-series-synthesizer.html"
  },
  {
    "id": "fractions-title",
    "name": "fractions",
    "title": "🔢 Fractions Calculator & Visualizer",
    "description": "Master fractions with calculations, visual representations, and step-by-step explanations. Perfect for students learning fractions!",
    "category": "Mathematics",
    "file": "fractions.html",
    "path": "cards/fractions.html"
  },
  {
    "id": "freelance-rate-calculator-title",
    "name": "freelance-rate-calculator",
    "title": "💼 Freelance Rate Calculator",
    "description": "Stop undercharging. Calculate your true sustainable hourly and day rates by factoring in unbillable admin time, self-employment taxes, equipment expenses, pension, and paid time off.",
    "category": "Finance & Money",
    "file": "freelance-rate-calculator.html",
    "path": "cards/freelance-rate-calculator.html"
  },
  {
    "id": "french-pronunciation-verbs-title",
    "name": "french-pronunciation-verbs",
    "title": "🇫🇷 French Verbs & Pronunciation",
    "description": "Master the most critical French irregular verbs (être, avoir, aller, faire) and unlock fluent French pronunciation with our guide to silent consonants and natural liaisons.",
    "category": "Writing & Language",
    "file": "french-pronunciation-verbs.html",
    "path": "cards/french-pronunciation-verbs.html"
  },
  {
    "id": "fuel-economy-mpg-converter-title",
    "name": "fuel-economy-mpg-converter",
    "title": "⛽ Fuel Economy MPG Converter",
    "description": "Convert between US MPG, UK (imperial) MPG, L/100 km and km/L. Optional trip distance estimates fuel used. US gallon = 3.785 L, imperial gallon = 4.546 L.",
    "category": "Productivity & Lifestyle",
    "file": "fuel-economy-mpg-converter.html",
    "path": "cards/fuel-economy-mpg-converter.html"
  },
  {
    "id": "fuel-mpg-litres-per-100km-converter-title",
    "name": "fuel-mpg-litres-per-100km-converter",
    "title": "⛽ Fuel Economy Converter: MPG ⇄ L/100km ⇄ km/L",
    "description": "Convert between UK MPG, US MPG, litres per 100 km, km per litre and miles per litre in one go — or calculate your real-world economy from a fill-up (miles driven and litres added). Includes a cost ...",
    "category": "Productivity & Lifestyle",
    "file": "fuel-mpg-litres-per-100km-converter.html",
    "path": "cards/fuel-mpg-litres-per-100km-converter.html"
  },
  {
    "id": "fuelcost-title",
    "name": "fuelcost",
    "title": "⛽ Fuel Cost Calculator Pro",
    "description": "Calculate trip fuel costs, compare vehicles, track carbon footprint, and find optimal routes. Real-time calculations with environmental impact!",
    "category": "Finance & Money",
    "file": "fuelcost.html",
    "path": "cards/fuelcost.html"
  },
  {
    "id": "function-terrain-3d-explorer-title",
    "name": "function-terrain-3d-explorer",
    "title": "⛰️ Function Terrain 3D Explorer",
    "description": "Type any z = f(x, y) formula and watch it become a spinning 3D mountain range. Safe built-in math parser (no eval), orbit/zoom controls, height colormaps and a random-function dice for beautiful ac...",
    "category": "Mathematics",
    "file": "function-terrain-3d-explorer.html",
    "path": "cards/function-terrain-3d-explorer.html"
  },
  {
    "id": "gallons-litres-pints-converter-title",
    "name": "gallons-litres-pints-converter",
    "title": "🍺 Gallons, Litres & Pints",
    "description": "UK pint is 568 ml; US pint is 473 ml. UK gallon is 4.54609 L; US gallon is 3.78541 L. Edit any box — the others follow using the same liquid volume. Cooking cups are a different mess.",
    "category": "Science & Engineering",
    "file": "gallons-litres-pints-converter.html",
    "path": "cards/gallons-litres-pints-converter.html"
  },
  {
    "id": "galton-board-central-limit-title",
    "name": "galton-board-central-limit",
    "title": "🔔 Galton Board & the Bell Curve",
    "description": "Every ball bounces left or right by pure chance — yet the pile always forms a perfect bell curve. This is the Central Limit Theorem: order emerging from randomness, and the reason so much of nature...",
    "category": "Mind-Blowing Demos",
    "file": "galton-board-central-limit.html",
    "path": "cards/galton-board-central-limit.html"
  },
  {
    "id": "garden-plant-spacing-calculator-title",
    "name": "garden-plant-spacing-calculator",
    "title": "🌱 Plant Spacing Calculator",
    "description": "How many plants fit a bed at a given spacing. Square grid is simplest; triangular (hex) packing fits about 15% more. Leave paths out of the length and width.",
    "category": "Home & DIY",
    "file": "garden-plant-spacing-calculator.html",
    "path": "cards/garden-plant-spacing-calculator.html"
  },
  {
    "id": "garden-task-title",
    "name": "garden-task",
    "title": "Smart Garden Task Planner",
    "description": "Plan, track, and grow your perfect garden with AI-powered suggestions and smart scheduling.",
    "category": "Productivity & Lifestyle",
    "file": "garden-task.html",
    "path": "cards/garden-task.html"
  },
  {
    "id": "gardening-title",
    "name": "gardening",
    "title": "🌿 Garden Planning Assistant",
    "description": "Plan, track, and optimize your garden with planting schedules, care reminders, and plant databases. Grow your perfect garden!",
    "category": "Productivity & Lifestyle",
    "file": "gardening.html",
    "path": "cards/gardening.html"
  },
  {
    "id": "gas-leak-carbon-monoxide-response-title",
    "name": "gas-leak-carbon-monoxide-response",
    "title": "🫁 Gas Leak & Carbon Monoxide Response",
    "description": "Three things people get wrong in the first two minutes, and all three can be fatal: what to touch when you smell gas, how to recognise carbon monoxide poisoning before someone collapses, and what a...",
    "category": "Survival & Emergency Readiness",
    "file": "gas-leak-carbon-monoxide-response.html",
    "path": "cards/gas-leak-carbon-monoxide-response.html"
  },
  {
    "id": "gcf-lcm-prime-factor-calculator-title",
    "name": "gcf-lcm-prime-factor-calculator",
    "title": "🧮 GCF, LCM & Prime Factors",
    "description": "Find the greatest common factor, least common multiple and prime factorisation of one or more integers. Euclidean algorithm for GCF; trial division up to √n for factors. Integers only, up to 12 dig...",
    "category": "Mathematics",
    "file": "gcf-lcm-prime-factor-calculator.html",
    "path": "cards/gcf-lcm-prime-factor-calculator.html"
  },
  {
    "id": "gdpr-ccpa-privacy-policy-generator-title",
    "name": "gdpr-ccpa-privacy-policy-generator",
    "title": "🛡️ Privacy Policy Generator",
    "description": "Generate legally-compliant Privacy Policies for websites, mobile apps, SaaS, and e-commerce stores. Includes GDPR, CCPA/CPRA, cookie consent, and third-party processor disclosures without paying re...",
    "category": "SaaS & Business Killers",
    "file": "gdpr-ccpa-privacy-policy-generator.html",
    "path": "cards/gdpr-ccpa-privacy-policy-generator.html"
  },
  {
    "id": "genetics-title",
    "name": "genetics",
    "title": "🧬 Genetics Laboratory",
    "description": "Explore genetics through interactive simulations, DNA analysis tools, and educational content. Perfect for students and enthusiasts!",
    "category": "Science & Engineering",
    "file": "genetics.html",
    "path": "cards/genetics.html"
  },
  {
    "id": "geodesic-area-parcel-calculator-title",
    "name": "geodesic-area-parcel-calculator",
    "title": "📐 Geodesic Area & Parcel Calculator",
    "description": "Type or click out a boundary and get its true area on the curved Earth using the spherical-excess formula — the same maths GIS packages use — alongside the flat-map answer so you can see exactly ho...",
    "category": "Science & Engineering",
    "file": "geodesic-area-parcel-calculator.html",
    "path": "cards/geodesic-area-parcel-calculator.html"
  },
  {
    "id": "geography-flag-capital-quiz-title",
    "name": "geography-flag-capital-quiz",
    "title": "🌍 Flag & Capital Quiz",
    "description": "Learn 40 countries with flip flashcards, then test yourself on capitals and flags. Streaks, scoring and fun facts make world geography stick.",
    "category": "Science & Engineering",
    "file": "geography-flag-capital-quiz.html",
    "path": "cards/geography-flag-capital-quiz.html"
  },
  {
    "id": "geography-title",
    "name": "geography",
    "title": "Geography Helper",
    "description": "Add countries, capitals, and notes to build your geography study list.",
    "category": "Science & Engineering",
    "file": "geography.html",
    "path": "cards/geography.html"
  },
  {
    "id": "geology-title",
    "name": "geology",
    "title": "Geology Tools & Facts",
    "description": "Explore geology concepts and discover fascinating facts about Earth's structure and processes.",
    "category": "Science & Engineering",
    "file": "geology.html",
    "path": "cards/geology.html"
  },
  {
    "id": "geometry-title",
    "name": "geometry",
    "title": "Geometry Calculator",
    "description": "Calculate areas, perimeters, and volumes for common shapes. Choose a shape, enter dimensions, and get results with formulas shown.",
    "category": "Mathematics",
    "file": "geometry.html",
    "path": "cards/geometry.html"
  },
  {
    "id": "german-cases-gender-title",
    "name": "german-cases-gender",
    "title": "🇩🇪 German Cases & Gender",
    "description": "Conquer the 4 German grammatical cases (Nominativ, Akkusativ, Dativ, Genitiv) and understand exactly how der, die, das shift based on subject, direct object, indirect recipient, or possession.",
    "category": "Writing & Language",
    "file": "german-cases-gender.html",
    "path": "cards/german-cases-gender.html"
  },
  {
    "id": "gift-title",
    "name": "gift",
    "title": "Gift Helper 🎁",
    "description": "Find the perfect gift with smart suggestions, reminders, and inspiration for every occasion.",
    "category": "Productivity & Lifestyle",
    "file": "gift.html",
    "path": "cards/gift.html"
  },
  {
    "id": "gitignore-template-builder-title",
    "name": "gitignore-template-builder",
    "title": "🙈 .gitignore Builder",
    "description": "Tick the stacks you use. Output is a combined .gitignore — copy into the repo root. Git still tracks files you already committed; git rm --cached those separately.",
    "category": "Algorithms & Computer Science",
    "file": "gitignore-template-builder.html",
    "path": "cards/gitignore-template-builder.html"
  },
  {
    "id": "go-outsideometer-title",
    "name": "go-outsideometer",
    "title": "🌤️ Go Outsideometer",
    "description": "A scientifically unserious instrument that measures how long it has been since you touched grass. Answer honestly, and it will tell you exactly how urgently you need to go outside — then give you a...",
    "category": "Productivity & Lifestyle",
    "file": "go-outsideometer.html",
    "path": "cards/go-outsideometer.html"
  },
  {
    "id": "goaltracker-title",
    "name": "goaltracker",
    "title": "Goal Tracker 🎯",
    "description": "Set, track, and achieve your goals with progress monitoring, milestones, and motivational reminders.",
    "category": "Productivity & Lifestyle",
    "file": "goaltracker.html",
    "path": "cards/goaltracker.html"
  },
  {
    "id": "golden-ratio-crop-calculator-title",
    "name": "golden-ratio-crop-calculator",
    "title": "φ Golden Ratio Crop Calculator",
    "description": "Grow or crop a rectangle to φ ≈ 1.618, place a golden-section grid, and convert any length into its complementary pair. Used by photographers and layout designers. Pure geometry — no image upload.",
    "category": "Productivity & Lifestyle",
    "file": "golden-ratio-crop-calculator.html",
    "path": "cards/golden-ratio-crop-calculator.html"
  },
  {
    "id": "golf-stableford-scorecard-calculator-title",
    "name": "golf-stableford-scorecard-calculator",
    "title": "⛳ Golf Stableford Points Calculator",
    "description": "Enter your course handicap and your gross score for each hole, and this works out the shots you receive, your net score, and the Stableford points per hole — the friendly format where a blob costs ...",
    "category": "Sports",
    "file": "golf-stableford-scorecard-calculator.html",
    "path": "cards/golf-stableford-scorecard-calculator.html"
  },
  {
    "id": "golf-whs-handicap-calculator-title",
    "name": "golf-whs-handicap-calculator",
    "title": "⛳ Golf WHS Handicap Calculator",
    "description": "The World Handicap System in two steps. Work out a round's Score Differential (what actually feeds your handicap), then turn a Handicap Index into your Course Handicap and Playing Handicap for that...",
    "category": "Sports",
    "file": "golf-whs-handicap-calculator.html",
    "path": "cards/golf-whs-handicap-calculator.html"
  },
  {
    "id": "gpa-title",
    "name": "gpa",
    "title": "🌍 International GPA Calculator",
    "description": "Calculate GPA for universities worldwide. Supports multiple grading systems and conversions.",
    "category": "Mathematics",
    "file": "gpa.html",
    "path": "cards/gpa.html"
  },
  {
    "id": "gps-coordinates-dms-decimal-title",
    "name": "gps-coordinates-dms-decimal",
    "title": "🧭 GPS DMS ⇄ Decimal",
    "description": "Convert latitude and longitude between degrees-minutes-seconds and decimal degrees. Decimal = degrees + minutes/60 + seconds/3600. South and west are negative. No map is loaded — nothing leaves the...",
    "category": "Science & Engineering",
    "file": "gps-coordinates-dms-decimal.html",
    "path": "cards/gps-coordinates-dms-decimal.html"
  },
  {
    "id": "grade-title",
    "name": "grade",
    "title": "Grade Calculator 📊",
    "description": "Calculate weighted grades, predict final scores, and see what you need to achieve your target grade.",
    "category": "Mathematics",
    "file": "grade.html",
    "path": "cards/grade.html"
  },
  {
    "id": "gradeweight-title",
    "name": "gradeweight",
    "title": "📊 Weighted Grade Calculator",
    "description": "Enter your assignments with weights and scores to calculate your final grade.",
    "category": "Mathematics",
    "file": "gradeweight.html",
    "path": "cards/gradeweight.html"
  },
  {
    "id": "grammar-proof-title",
    "name": "grammar-proof",
    "title": "Grammar Proofreader ✍️",
    "description": "Check text for grammar, spelling, punctuation, and style issues. Get suggestions and explanations to improve your writing.",
    "category": "Writing & Language",
    "file": "grammar-proof.html",
    "path": "cards/grammar-proof.html"
  },
  {
    "id": "graphing-calculator-title",
    "name": "graphing-calculator",
    "title": "🌐 Smart Graphing Calculator",
    "description": "Interactive math visualization: Plot functions, find roots, compute derivatives/integrals, solve equations, and create beautiful graphs. Perfect for students, teachers, and professionals.",
    "category": "Mathematics",
    "file": "graphing-calculator.html",
    "path": "cards/graphing-calculator.html"
  },
  {
    "id": "gravel-calculator-title",
    "name": "gravel-calculator",
    "title": "🪨 Gravel & Aggregate Calculator",
    "description": "Calculate how much gravel, slate, chippings, or aggregate you need for driveways, paths, patios, or garden beds. Includes tonnes, bulk bags, and cost.",
    "category": "Home & DIY",
    "file": "gravel-calculator.html",
    "path": "cards/gravel-calculator.html"
  },
  {
    "id": "gravitational-lensing-black-hole-title",
    "name": "gravitational-lensing-black-hole",
    "title": "🕳️ Gravitational Lensing Lab",
    "description": "General Relativity astrophysics exhibit. Drag a supermassive Schwarzschild black hole across cosmic starfields to observe Einstein rings and photon deflection.",
    "category": "Science & Engineering",
    "file": "gravitational-lensing-black-hole.html",
    "path": "cards/gravitational-lensing-black-hole.html"
  },
  {
    "id": "gravitational-n-body-galaxy-collision-title",
    "name": "gravitational-n-body-galaxy-collision",
    "title": "🌌 Galaxy Collision & Tidal Tails",
    "description": "Gravitational N-body astrophysical simulation. Watch two disk galaxies collide as differential tidal forces eject long parabolic stellar bridges and tails.",
    "category": "Science & Engineering",
    "file": "gravitational-n-body-galaxy-collision.html",
    "path": "cards/gravitational-n-body-galaxy-collision.html"
  },
  {
    "id": "great-circle-route-planner-title",
    "name": "great-circle-route-planner",
    "title": "✈️ Great-Circle Route Planner",
    "description": "Why does a London–Tokyo flight arc over Siberia? Compute the true shortest path between any two points — Vincenty distance on the real ellipsoid, initial and final bearings, waypoints along the way...",
    "category": "Science & Engineering",
    "file": "great-circle-route-planner.html",
    "path": "cards/great-circle-route-planner.html"
  },
  {
    "id": "great-minds-quote-explorer-title",
    "name": "great-minds-quote-explorer",
    "title": "💬 Great Minds Quote Explorer",
    "description": "40 inspiring quotes from history's greatest scientists, inventors and thinkers — each with context about who said it and why it matters. Search, filter by theme, save favourites.",
    "category": "Productivity & Lifestyle",
    "file": "great-minds-quote-explorer.html",
    "path": "cards/great-minds-quote-explorer.html"
  },
  {
    "id": "grid-reference-trainer-title",
    "name": "grid-reference-trainer",
    "title": "🧭 Grid Reference Trainer (OS)",
    "description": "Learn four- and six-figure Ordnance Survey grid references on a visual grid — remember: eastings (across) first, northings (up) second.",
    "category": "MrProphecy Arcade",
    "file": "grid-reference-trainer.html",
    "path": "cards/grid-reference-trainer.html"
  },
  {
    "id": "grief-companion-title",
    "name": "grief-companion",
    "title": "🕯️ Grief Companion",
    "description": "There is nothing to fix here, and nothing you are supposed to be over by now. What this does is help with the two things grief actually makes hard: getting through an ordinary day, and not being bl...",
    "category": "Wellbeing & Community",
    "file": "grief-companion.html",
    "path": "cards/grief-companion.html"
  },
  {
    "id": "grocerybudget-title",
    "name": "grocerybudget",
    "title": "🛒 Grocery Budget Tracker",
    "description": "Track your grocery spending, categorize items, and stay within your budget with smart insights.",
    "category": "Finance & Money",
    "file": "grocerybudget.html",
    "path": "cards/grocerybudget.html"
  },
  {
    "id": "grounding-breathing-coach-title",
    "name": "grounding-breathing-coach",
    "title": "🫁 Grounding & Breathing Coach",
    "description": "For the moments when your body has decided there is an emergency and your head knows there is not one. Nothing here needs signing up to, nothing is recorded, and it works offline once the page is o...",
    "category": "Wellbeing & Community",
    "file": "grounding-breathing-coach.html",
    "path": "cards/grounding-breathing-coach.html"
  },
  {
    "id": "grout-adhesive-calculator-title",
    "name": "grout-adhesive-calculator",
    "title": "🧱 Grout & Tile Adhesive Calculator",
    "description": "The tiles are one thing — the grout and adhesive to fix them are another. Enter the tiled area, tile size and joint width to work out how much grout and thinset to mix.",
    "category": "Home & DIY",
    "file": "grout-adhesive-calculator.html",
    "path": "cards/grout-adhesive-calculator.html"
  },
  {
    "id": "guitar-fret-calculator-title",
    "name": "guitar-fret-calculator",
    "title": "🎸 Guitar Fret Position Calculator",
    "description": "Equal-temperament fret rule: distance from nut to fret n = L × (1 − 1/2^(n/12)) where L is scale length. 12th fret is the octave (halfway). Not a CNC file.",
    "category": "Music & Audio",
    "file": "guitar-fret-calculator.html",
    "path": "cards/guitar-fret-calculator.html"
  },
  {
    "id": "gymnastics-score-calculator-title",
    "name": "gymnastics-score-calculator",
    "title": "🤸 Gymnastics Score Calculator",
    "description": "A gymnastics score is difficulty plus execution. Enter the D-score, tick the deductions, and this works out the E-score (out of 10) and the final total.",
    "category": "Sports",
    "file": "gymnastics-score-calculator.html",
    "path": "cards/gymnastics-score-calculator.html"
  },
  {
    "id": "gyroscopic-precession-dynamics-title",
    "name": "gyroscopic-precession-dynamics",
    "title": "🧭 Gyroscopic Precession Lab",
    "description": "Explore rigid body rotational mechanics ($\\boldsymbol{\\tau} = \\boldsymbol{\\Omega}_p \\times \\mathbf{L}$). Calculate steady precession velocity ($\\Omega_p = \\frac{mgr}{I_z \\omega_s}$), nutation frequ...",
    "category": "Science & Engineering",
    "file": "gyroscopic-precession-dynamics.html",
    "path": "cards/gyroscopic-precession-dynamics.html"
  },
  {
    "id": "habit-streak-matrix-tracker-title",
    "name": "habit-streak-matrix-tracker",
    "title": "🔥 Habit Streak Grid",
    "description": "Track daily habits and build unstoppable momentum with a GitHub-style contribution heat map. Saves automatically in your browser.",
    "category": "Productivity & Lifestyle",
    "file": "habit-streak-matrix-tracker.html",
    "path": "cards/habit-streak-matrix-tracker.html"
  },
  {
    "id": "habit-title",
    "name": "habit",
    "title": "📈 Habit Tracker",
    "description": "Build consistent habits with visual streaks and daily tracking. Save your progress automatically!",
    "category": "Productivity & Lifestyle",
    "file": "habit.html",
    "path": "cards/habit.html"
  },
  {
    "id": "handball-scorekeeper-title",
    "name": "handball-scorekeeper",
    "title": "🤾 Handball Scorekeeper",
    "description": "Two halves, goals, and the two-minute suspensions that define the game. Tap to score, track each team's suspensions, and keep the running total.",
    "category": "Sports",
    "file": "handball-scorekeeper.html",
    "path": "cards/handball-scorekeeper.html"
  },
  {
    "id": "harmonic-orbit-gravitational-soundscape-title",
    "name": "harmonic-orbit-gravitational-soundscape",
    "title": "🪐 HarmonicOrbit Loom",
    "description": "An evolving celestial music box. Launch orbiting planets into gravitational fields. As orbital bodies cross harmonic resonance spokes, they trigger soothing mathematical melodies synthesized in rea...",
    "category": "Interactive Art & Living Worlds",
    "file": "harmonic-orbit-gravitational-soundscape.html",
    "path": "cards/harmonic-orbit-gravitational-soundscape.html"
  },
  {
    "id": "hash-checker-title",
    "name": "hash-checker",
    "title": "🔐 File Hash Checker",
    "description": "Verify file integrity and calculate cryptographic hashes. Compare hashes to verify file authenticity!",
    "category": "Productivity & Lifestyle",
    "file": "hash-checker.html",
    "path": "cards/hash-checker.html"
  },
  {
    "id": "hash-crypto-encoder-suite-title",
    "name": "hash-crypto-encoder-suite",
    "title": "🔐 Crypto & Hash Suite",
    "description": "Generate cryptographic hashes (SHA-256, SHA-512, MD5), HMAC signatures, and multi-format encodings (Base64, Hex, URL). Fast, client-side, and zero-knowledge.",
    "category": "Productivity & Lifestyle",
    "file": "hash-crypto-encoder-suite.html",
    "path": "cards/hash-crypto-encoder-suite.html"
  },
  {
    "id": "hash-generator-title",
    "name": "hash-generator",
    "title": "🔒 Hash Generator",
    "description": "Generate cryptographic hashes instantly. Supports MD5, SHA-1, SHA-256, SHA-384, SHA-512. All processing happens in your browser — nothing is sent to any server.",
    "category": "Algorithms & Computer Science",
    "file": "hash-generator.html",
    "path": "cards/hash-generator.html"
  },
  {
    "id": "hat-size-converter-title",
    "name": "hat-size-converter",
    "title": "🎩 Hat Size Converter",
    "description": "Convert head circumference to UK, US and cm hat sizes. US size ≈ circumference in inches ÷ π. Measure just above the ears, level around the widest part. Felt hats often want a snug fit; straw can r...",
    "category": "Productivity & Lifestyle",
    "file": "hat-size-converter.html",
    "path": "cards/hat-size-converter.html"
  },
  {
    "id": "heartrate-title",
    "name": "heartrate",
    "title": "❤️ Heart Rate Zones Calculator",
    "description": "Calculate training zones, VO₂ max estimates, heart rate variability (HRV), and recovery metrics. Professional-grade analytics for athletes!",
    "category": "Health & Fitness",
    "file": "heartrate.html",
    "path": "cards/heartrate.html"
  },
  {
    "id": "heat-cold-exposure-survival-calc-title",
    "name": "heat-cold-exposure-survival-calc",
    "title": "🥶 Heat & Cold Exposure Calculator",
    "description": "Temperature alone lies. Wind takes heat off you far faster than the number suggests, humidity stops you cooling yourself down, and wet clothing changes everything again. This works out what the air...",
    "category": "Survival & Emergency Readiness",
    "file": "heat-cold-exposure-survival-calc.html",
    "path": "cards/heat-cold-exposure-survival-calc.html"
  },
  {
    "id": "heat-index-calculator-title",
    "name": "heat-index-calculator",
    "title": "🥵 Heat Index Calculator",
    "description": "NWS Rothfusz heat index from shade air temperature and relative humidity. Officially for ≥ 27 °C. Full sun can feel several degrees worse. Not medical advice — heatstroke is an emergency.",
    "category": "Science & Engineering",
    "file": "heat-index-calculator.html",
    "path": "cards/heat-index-calculator.html"
  },
  {
    "id": "heightmap-3d-sculptor-title",
    "name": "heightmap-3d-sculptor",
    "title": "⛰️ Heightmap 3D Sculptor",
    "description": "Paint mountains with your pointer on the map (left) and watch a living 3D island grow (right) — with beaches, forests, snowcaps, animated water and erosion. Or generate procedural islands, ridges a...",
    "category": "Interactive Art & Living Worlds",
    "file": "heightmap-3d-sculptor.html",
    "path": "cards/heightmap-3d-sculptor.html"
  },
  {
    "id": "heraldry-blazon-workshop-title",
    "name": "heraldry-blazon-workshop",
    "title": "🛡️ The Blazon Workshop",
    "description": "A teaching coat, not a grant. Choose a field, an ordinary and a charge. The plaque writes the blazon in the old word-order: metal or colour first, then the ordinary, then what stands upon it. Rule ...",
    "category": "Museum & Collection",
    "file": "heraldry-blazon-workshop.html",
    "path": "cards/heraldry-blazon-workshop.html"
  },
  {
    "id": "herb-drug-interaction-checker-title",
    "name": "herb-drug-interaction-checker",
    "title": "⚠️ Herb & Prescription Safety",
    "description": "Clinical botanical pharmacodynamics checker. Cross-references herbal compounds against prescription drug classes to prevent CYP450 enzyme conflicts and adverse events.",
    "category": "Natural Remedies & Herbs",
    "file": "herb-drug-interaction-checker.html",
    "path": "cards/herb-drug-interaction-checker.html"
  },
  {
    "id": "herbal-infusion-decoction-timer-title",
    "name": "herbal-infusion-decoction-timer",
    "title": "🫖 Herbal Tea & Extraction Timer",
    "description": "Scientific phytotherapy extraction guide. Tailors thermal temperatures, liquid-to-herb ratios, and brew times between volatile floral infusions and dense root decoctions.",
    "category": "Natural Remedies & Herbs",
    "file": "herbal-infusion-decoction-timer.html",
    "path": "cards/herbal-infusion-decoction-timer.html"
  },
  {
    "id": "herbal-salve-beeswax-ratio-title",
    "name": "herbal-salve-beeswax-ratio",
    "title": "🧴 Herbal Salve & Balm Crafter",
    "description": "Formulate medicinal balms and herbal salves. Calculates exact beeswax-to-infused-oil ratios for soft rubs, standard tins, or heat-resistant summer lip balms.",
    "category": "Natural Remedies & Herbs",
    "file": "herbal-salve-beeswax-ratio.html",
    "path": "cards/herbal-salve-beeswax-ratio.html"
  },
  {
    "id": "herbal-tincture-ratio-calc-title",
    "name": "herbal-tincture-ratio-calc",
    "title": "🌿 Herbal Tincture Ratio Calc",
    "description": "Pharmacopoeial weight-to-volume maceration calculator. Formulates herb-to-solvent ratios (1:5 dry / 1:2 fresh) and calculates alcohol-to-water dilution for target phytochemical solubility.",
    "category": "Natural Remedies & Herbs",
    "file": "herbal-tincture-ratio-calc.html",
    "path": "cards/herbal-tincture-ratio-calc.html"
  },
  {
    "id": "hex-decimal-title",
    "name": "hex-decimal",
    "title": "🔢 Hex & Decimal Converter",
    "description": "Convert between hexadecimal, decimal, binary, octal, and ASCII with bitwise operations. Essential for developers, modders, and reverse engineering!",
    "category": "Mathematics",
    "file": "hex-decimal.html",
    "path": "cards/hex-decimal.html"
  },
  {
    "id": "hike-time-planner-title",
    "name": "hike-time-planner",
    "title": "🥾 Hike & Walk Time Planner",
    "description": "Built on Naismith's Rule, the estimate mountain rescue has used for a century: allow an hour for every 5 km, plus a minute for every 10 m climbed. Then it adds the two things that actually decide w...",
    "category": "Science & Engineering",
    "file": "hike-time-planner.html",
    "path": "cards/hike-time-planner.html"
  },
  {
    "id": "history-title",
    "name": "history",
    "title": "📜 Advanced History Timeline Builder",
    "description": "Create interactive timelines, explore historical databases, and visualize events across civilizations. Perfect for students, educators, and history enthusiasts!",
    "category": "Productivity & Lifestyle",
    "file": "history.html",
    "path": "cards/history.html"
  },
  {
    "id": "hmrc-mileage-allowance-calculator-title",
    "name": "hmrc-mileage-allowance-calculator",
    "title": "🚗 HMRC Mileage Allowance",
    "description": "Tax-free Approved Mileage Allowance Payments for 2026/27: cars and vans 55p for the first 10,000 business miles then 25p; motorcycles 24p; bicycles 20p; plus 5p per passenger per mile. Rates from G...",
    "category": "Finance & Money",
    "file": "hmrc-mileage-allowance-calculator.html",
    "path": "cards/hmrc-mileage-allowance-calculator.html"
  },
  {
    "id": "holiday-entitlement-calculator-title",
    "name": "holiday-entitlement-calculator",
    "title": "🌴 Holiday Entitlement & Pro-Rata Calculator",
    "description": "Work out statutory UK holiday for part-timers, mid-year starters and leavers, and irregular-hours staff — including the 12.07% accrual method. Employers get this wrong constantly. Nothing you enter...",
    "category": "Finance & Money",
    "file": "holiday-entitlement-calculator.html",
    "path": "cards/holiday-entitlement-calculator.html"
  },
  {
    "id": "hominin-timeline-hall-title",
    "name": "hominin-timeline-hall",
    "title": "🧬 The Hominin Corridor",
    "description": "Not a ladder. A bush of species, several of which overlapped. Brain volumes are typical adult means; dates are first-to-last fossil appearances as currently argued. The corridor will not tell you w...",
    "category": "Museum & Collection",
    "file": "hominin-timeline-hall.html",
    "path": "cards/hominin-timeline-hall.html"
  },
  {
    "id": "horizon-line-of-sight-calculator-title",
    "name": "horizon-line-of-sight-calculator",
    "title": "🌅 Horizon & Line-of-Sight Calculator",
    "description": "How far can you actually see, and how much of that distant hill, ship or radio mast is hidden behind the bulge of the Earth? Enter two heights and a distance and get the geometric answer, the refra...",
    "category": "Science & Engineering",
    "file": "horizon-line-of-sight-calculator.html",
    "path": "cards/horizon-line-of-sight-calculator.html"
  },
  {
    "id": "horsepower-kw-torque-converter-title",
    "name": "horsepower-kw-torque-converter",
    "title": "🏎️ Horsepower, kW & Torque",
    "description": "Convert mechanical horsepower, metric PS and kilowatts, and compute power from torque × RPM. 1 hp = 745.7 W; 1 PS = 735.5 W. Power (kW) = torque (N·m) × RPM / 9549.",
    "category": "Science & Engineering",
    "file": "horsepower-kw-torque-converter.html",
    "path": "cards/horsepower-kw-torque-converter.html"
  },
  {
    "id": "hourly-to-annual-salary-converter-title",
    "name": "hourly-to-annual-salary-converter",
    "title": "💷 Hourly ⇄ Annual Salary",
    "description": "Convert an hourly rate to a yearly salary (and back) using your hours per week and weeks per year. Defaults match a UK full-time week. Gross pay only — tax is not deducted.",
    "category": "Finance & Money",
    "file": "hourly-to-annual-salary-converter.html",
    "path": "cards/hourly-to-annual-salary-converter.html"
  },
  {
    "id": "household-emergency-plan-title",
    "name": "household-emergency-plan",
    "title": "🚨 Household Emergency Plan",
    "description": "Fill this in once on a calm afternoon and it turns a frightening night into a set of steps everyone already knows. It stays on your device, and you can print or copy it to stick on the fridge — whi...",
    "category": "Wellbeing & Community",
    "file": "household-emergency-plan.html",
    "path": "cards/household-emergency-plan.html"
  },
  {
    "id": "household-title",
    "name": "household",
    "title": "🏠 Advanced Household Chore Tracker",
    "description": "Manage household chores, assign tasks, set schedules, and track completion with reminders. Perfect for families and shared living!",
    "category": "Productivity & Lifestyle",
    "file": "household.html",
    "path": "cards/household.html"
  },
  {
    "id": "houseplant-matchmaker-title",
    "name": "houseplant-matchmaker",
    "title": "🪴 Houseplant Matchmaker",
    "description": "The dating app for you and a plant. Answer honestly about your light, your watering habits and your pets, and it will set you up with a houseplant that can actually survive you.",
    "category": "Productivity & Lifestyle",
    "file": "houseplant-matchmaker.html",
    "path": "cards/houseplant-matchmaker.html"
  },
  {
    "id": "htaccess-redirect-generator-title",
    "name": "htaccess-redirect-generator",
    "title": "🔀 .htaccess Redirect Generator",
    "description": "Build Apache mod_rewrite rules for 301/302 redirects, HTTP→HTTPS and www/apex canonical hosts. Output is a snippet to paste into .htaccess. Review before deploying — a bad rewrite loops a site.",
    "category": "Algorithms & Computer Science",
    "file": "htaccess-redirect-generator.html",
    "path": "cards/htaccess-redirect-generator.html"
  },
  {
    "id": "html-css-minifier-title",
    "name": "html-css-minifier",
    "title": "📦 HTML / CSS Minifier",
    "description": "Strip comments and collapse idle whitespace in HTML or CSS. Not a full parser — keep <pre> and <textarea> out of the input, and do not minify JavaScript here. Local only.",
    "category": "Algorithms & Computer Science",
    "file": "html-css-minifier.html",
    "path": "cards/html-css-minifier.html"
  },
  {
    "id": "html-entity-encoder-decoder-title",
    "name": "html-entity-encoder-decoder",
    "title": "🔤 HTML Entity Encoder & Decoder",
    "description": "Escape text for safe HTML display, decode named or numeric entities, and inspect the characters in a string. Choose readable entities for the five HTML-sensitive characters or numeric entities for ...",
    "category": "SaaS & Business Killers",
    "file": "html-entity-encoder-decoder.html",
    "path": "cards/html-entity-encoder-decoder.html"
  },
  {
    "id": "html-entity-encoder-title",
    "name": "html-entity-encoder",
    "title": "🔤 HTML Entity Encoder / Decoder",
    "description": "Encode special characters to HTML entities and decode them back. Essential for web development and email templates.",
    "category": "Algorithms & Computer Science",
    "file": "html-entity-encoder.html",
    "path": "cards/html-entity-encoder.html"
  },
  {
    "id": "html-table-generator-title",
    "name": "html-table-generator",
    "title": "📋 HTML Table Generator",
    "description": "Turn a quick list of headers and rows into accessible, escaped HTML table markup with a live preview. Paste pipe- or comma-separated data, add an optional caption, and copy code that works cleanly ...",
    "category": "SaaS & Business Killers",
    "file": "html-table-generator.html",
    "path": "cards/html-table-generator.html"
  },
  {
    "id": "html-to-markdown-converter-title",
    "name": "html-to-markdown-converter",
    "title": "📝 HTML to Markdown Converter",
    "description": "A practical subset: headings, paragraphs, links, images, lists, bold/italic, code, blockquotes, hr. Scripts and styles are dropped. Not a full CommonMark round-trip.",
    "category": "Algorithms & Computer Science",
    "file": "html-to-markdown-converter.html",
    "path": "cards/html-to-markdown-converter.html"
  },
  {
    "id": "http-status-code-encyclopedia-title",
    "name": "http-status-code-encyclopedia",
    "title": "📡 HTTP Status Code Encyclopedia",
    "description": "Look up any HTTP status code, filter by class, and copy a one-line explanation. Covers the registered 1xx–5xx codes developers hit in the wild. Entirely offline.",
    "category": "Algorithms & Computer Science",
    "file": "http-status-code-encyclopedia.html",
    "path": "cards/http-status-code-encyclopedia.html"
  },
  {
    "id": "http-status-codes-title",
    "name": "http-status-codes",
    "title": "🌐 HTTP Status Code Reference",
    "description": "Complete reference of all HTTP status codes with descriptions, causes, and solutions. Search and filter instantly.",
    "category": "Algorithms & Computer Science",
    "file": "http-status-codes.html",
    "path": "cards/http-status-codes.html"
  },
  {
    "id": "huffman-coding-compression-title",
    "name": "huffman-coding-compression",
    "title": "🗜️ Huffman Coding: How Compression Works",
    "description": "Type any text and watch it get smaller: common letters get short codes, rare ones get long codes, and the result is the exact same idea behind ZIP, PNG and MP3. The tree is the codebook, drawn for ...",
    "category": "Algorithms & Computer Science",
    "file": "huffman-coding-compression.html",
    "path": "cards/huffman-coding-compression.html"
  },
  {
    "id": "hummingbird-nectar-spoilage-title",
    "name": "hummingbird-nectar-spoilage",
    "title": "🌸 Hummingbird Nectar & Spoilage",
    "description": "Formulate natural 20% sucrose syrup and monitor microbial fermentation rates. Calculates exact water-to-cane-sugar ratios and temperature-driven spoilage limits.",
    "category": "Birdwatching & Ornithology",
    "file": "hummingbird-nectar-spoilage.html",
    "path": "cards/hummingbird-nectar-spoilage.html"
  },
  {
    "id": "hurricane-engine-title",
    "name": "hurricane-engine",
    "title": "🌀 Hurricane Engine",
    "description": "A rotating tropical cyclone whose intensity is set by Emanuel's maximum potential intensity: sea-surface temperature, Coriolis (latitude) and vertical wind shear. Warm water and a spinning Earth bu...",
    "category": "Interactive Art & Living Worlds",
    "file": "hurricane-engine.html",
    "path": "cards/hurricane-engine.html"
  },
  {
    "id": "hydration-title",
    "name": "hydration",
    "title": "💧 Daily Hydration Calculator",
    "description": "Calculate your personalized daily water intake needs. Track your progress throughout the day!",
    "category": "Health & Fitness",
    "file": "hydration.html",
    "path": "cards/hydration.html"
  },
  {
    "id": "hypercube-4d-explorer-title",
    "name": "hypercube-4d-explorer",
    "title": "🧊 Hypercube 4D Explorer",
    "description": "Spin a real tesseract — a 4D cube — with true four-dimensional rotation. Twist the XW, YW and ZW planes that don't exist in our world, slide 4D perspective until it turns inside-out, and meet its s...",
    "category": "Mind-Blowing Demos",
    "file": "hypercube-4d-explorer.html",
    "path": "cards/hypercube-4d-explorer.html"
  },
  {
    "id": "hyperfocal-depth-of-field-calculator-title",
    "name": "hyperfocal-depth-of-field-calculator",
    "title": "📷 Hyperfocal & Depth of Field",
    "description": "Hyperfocal distance H = f² / (N × c) + f. Focus there and everything from H/2 to infinity is acceptably sharp. Circle of confusion defaults: full frame 0.030 mm, APS-C 0.019 mm, Micro Four Thirds 0...",
    "category": "Productivity & Lifestyle",
    "file": "hyperfocal-depth-of-field-calculator.html",
    "path": "cards/hyperfocal-depth-of-field-calculator.html"
  },
  {
    "id": "iban-validator-formatter-title",
    "name": "iban-validator-formatter",
    "title": "🏦 IBAN Validator & Formatter",
    "description": "Check an International Bank Account Number with the ISO 13616 MOD-97 algorithm, then pretty-print it in groups of four. This confirms the check digits only — it cannot prove an account exists.",
    "category": "Algorithms & Computer Science",
    "file": "iban-validator-formatter.html",
    "path": "cards/iban-validator-formatter.html"
  },
  {
    "id": "ice-hockey-goalie-stats-title",
    "name": "ice-hockey-goalie-stats",
    "title": "🏒 Ice Hockey Goalie Stats",
    "description": "Turn a goalie's box score into the numbers that matter: goals-against average, save percentage, and a win–loss record — with a read on how good they actually are.",
    "category": "Sports",
    "file": "ice-hockey-goalie-stats.html",
    "path": "cards/ice-hockey-goalie-stats.html"
  },
  {
    "id": "ics-event-builder-title",
    "name": "ics-event-builder",
    "title": "📅 ICS Event Builder",
    "description": "Make a .ics file any calendar app can import. Times are written as floating local (no time-zone math). All-day events use DATE values.",
    "category": "Algorithms & Computer Science",
    "file": "ics-event-builder.html",
    "path": "cards/ics-event-builder.html"
  },
  {
    "id": "idealweight-title",
    "name": "idealweight",
    "title": "⚖️ Ideal Weight & BMI",
    "description": "Get a comprehensive analysis of your ideal weight range using multiple scientific formulas and personalized factors.",
    "category": "Health & Fitness",
    "file": "idealweight.html",
    "path": "cards/idealweight.html"
  },
  {
    "id": "ieee-754-converter-title",
    "name": "ieee-754-converter",
    "title": "🔢 IEEE-754 Converter",
    "description": "32-bit binary32 (float) and 64-bit binary64 (double) bit patterns via typed arrays. Paste a decimal, hex (0x…) or 32/64-bit 0/1 string.",
    "category": "Algorithms & Computer Science",
    "file": "ieee-754-converter.html",
    "path": "cards/ieee-754-converter.html"
  },
  {
    "id": "image-base64-data-url-converter-title",
    "name": "image-base64-data-url-converter",
    "title": "🖼️ Image to Base64 Studio",
    "description": "Convert images to Base64 data URLs for inline CSS & HTML embedding, or decode Base64 strings back into downloadable images.",
    "category": "Productivity & Lifestyle",
    "file": "image-base64-data-url-converter.html",
    "path": "cards/image-base64-data-url-converter.html"
  },
  {
    "id": "image-compressor-resizer-offline-title",
    "name": "image-compressor-resizer-offline",
    "title": "🖼️ Image Compressor & Resizer (100% Offline)",
    "description": "Shrink photos for email, web or forms without uploading them anywhere. Drop in JPG, PNG, WebP or HEIC-converted images, set a maximum width or a target file size, choose the output format and quali...",
    "category": "Productivity & Lifestyle",
    "file": "image-compressor-resizer-offline.html",
    "path": "cards/image-compressor-resizer-offline.html"
  },
  {
    "id": "image-optimiser-studio-title",
    "name": "image-optimiser-studio",
    "title": "🗜️ Image Optimiser Studio",
    "description": "Batch-shrink photos and screenshots without uploading a single byte. Drop files in, pick a target size and format, and watch the real compressed file size update as you move the quality slider. Exp...",
    "category": "SaaS & Business Killers",
    "file": "image-optimiser-studio.html",
    "path": "cards/image-optimiser-studio.html"
  },
  {
    "id": "impossible-object-viewer-title",
    "name": "impossible-object-viewer",
    "title": "🌀 Impossible Object Viewer",
    "description": "A spinning Necker cube that flips inside your head, a Penrose triangle with an X-ray slider that reveals the cheat, and endless stairs with a ball that descends forever. True 3D rotation of impossi...",
    "category": "Mind-Blowing Demos",
    "file": "impossible-object-viewer.html",
    "path": "cards/impossible-object-viewer.html"
  },
  {
    "id": "inductance-calculator-title",
    "name": "inductance-calculator",
    "title": "⚡ Inductance Calculator",
    "description": "Professional inductance calculator with real-time visualization, multiple coil types, and comprehensive electrical analysis.",
    "category": "Science & Engineering",
    "file": "inductance-calculator.html",
    "path": "cards/inductance-calculator.html"
  },
  {
    "id": "inflation-title",
    "name": "inflation",
    "title": "📉 Inflation Impact Calculator",
    "description": "Calculate real-world purchasing power with historical data, multiple currencies, and personalized financial scenarios.",
    "category": "Finance & Money",
    "file": "inflation.html",
    "path": "cards/inflation.html"
  },
  {
    "id": "ingredient-scaler-title",
    "name": "ingredient-scaler",
    "title": "🧮 Recipe Ingredient Scaler",
    "description": "Perfectly scale any recipe with smart parsing, automatic unit conversions, and kitchen-tested measurements.",
    "category": "Productivity & Lifestyle",
    "file": "ingredient-scaler.html",
    "path": "cards/ingredient-scaler.html"
  },
  {
    "id": "instrument-care-title",
    "name": "instrument-care",
    "title": "🎶 Instrument Care Guide",
    "description": "Get detailed care instructions with maintenance schedules, required tools, and professional tips for your specific instrument.",
    "category": "Music & Audio",
    "file": "instrument-care.html",
    "path": "cards/instrument-care.html"
  },
  {
    "id": "insulation-calculator-title",
    "name": "insulation-calculator",
    "title": "🧊 Insulation Savings Calculator",
    "description": "Estimate how much you could save by insulating your loft, walls, or floor. Based on UK energy prices.",
    "category": "Home & DIY",
    "file": "insulation-calculator.html",
    "path": "cards/insulation-calculator.html"
  },
  {
    "id": "interest-title",
    "name": "interest",
    "title": "💰 Compound Interest Growth Visualiser",
    "description": "Calculate how your money multiplies over time with compound interest—the 8th wonder of the world!",
    "category": "Finance & Money",
    "file": "interest.html",
    "path": "cards/interest.html"
  },
  {
    "id": "intermittent-fasting-window-planner-title",
    "name": "intermittent-fasting-window-planner",
    "title": "⏳ Intermittent Fasting Window",
    "description": "Pick a 16:8, 18:6, 20:4 or custom fast and see today’s eat-from / eat-until times. Educational scheduling only — not medical advice, and not for anyone who is pregnant, under 18, or has an eating-d...",
    "category": "Health & Fitness",
    "file": "intermittent-fasting-window-planner.html",
    "path": "cards/intermittent-fasting-window-planner.html"
  },
  {
    "id": "interval-trainer-title",
    "name": "interval-trainer",
    "title": "🎵 Interval Ear Trainer",
    "description": "Essential for musicians: Learn to identify intervals by ear. Perfect for singers, composers, and anyone learning music theory!",
    "category": "Music & Audio",
    "file": "interval-trainer.html",
    "path": "cards/interval-trainer.html"
  },
  {
    "id": "inventory-reorder-point-planner-title",
    "name": "inventory-reorder-point-planner",
    "title": "📦 Inventory Reorder Point Planner",
    "description": "Calculate when to reorder stock using sales velocity, supplier lead time and safety stock. All calculations stay in your browser.",
    "category": "SaaS & Business Killers",
    "file": "inventory-reorder-point-planner.html",
    "path": "cards/inventory-reorder-point-planner.html"
  },
  {
    "id": "inverter-sizing-title",
    "name": "inverter-sizing",
    "title": "⚡ Solar Inverter Sizing",
    "description": "Essential for solar/off-grid setups: Calculate the right inverter size for your needs. Always consult a professional before installation!",
    "category": "Science & Engineering",
    "file": "inverter-sizing.html",
    "path": "cards/inverter-sizing.html"
  },
  {
    "id": "investment-title",
    "name": "investment",
    "title": "📈 Investment Growth Calculator",
    "description": "Watch your money multiply: Calculate how small investments today can grow into significant wealth over time through compounding.",
    "category": "Finance & Money",
    "file": "investment.html",
    "path": "cards/investment.html"
  },
  {
    "id": "invoice-billing-pdf-generator-title",
    "name": "invoice-billing-pdf-generator",
    "title": "🧾 InvoiceForge Generator",
    "description": "Generate clean, client-ready invoices with zero watermarks. Calculates multi-currency line items, tax, discounts, and payment terms with 1-click browser print to PDF. Instant browser-based invoicin...",
    "category": "SaaS & Business Killers",
    "file": "invoice-billing-pdf-generator.html",
    "path": "cards/invoice-billing-pdf-generator.html"
  },
  {
    "id": "invoice-late-fee-calculator-title",
    "name": "invoice-late-fee-calculator",
    "title": "🧾 Invoice Late Fee Calculator",
    "description": "Calculate statutory or agreed late-payment interest and a clear updated invoice total. All calculations stay in your browser.",
    "category": "Finance & Money",
    "file": "invoice-late-fee-calculator.html",
    "path": "cards/invoice-late-fee-calculator.html"
  },
  {
    "id": "ir35-comparator-title",
    "name": "ir35-comparator",
    "title": "⚖️ IR35 Inside vs Outside Comparator",
    "description": "Compare take-home pay as a contractor: inside IR35 through an umbrella company versus outside IR35 through your own limited company. Editable tax rates, full working shown, nothing leaves your devi...",
    "category": "Finance & Money",
    "file": "ir35-comparator.html",
    "path": "cards/ir35-comparator.html"
  },
  {
    "id": "irregular-verbs-trainer-title",
    "name": "irregular-verbs-trainer",
    "title": "🔁 Irregular Verbs Trainer",
    "description": "Drill the English verbs that refuse to follow the rules — go/went/gone, swim/swam/swum — in 8-question rounds, with a full reference table and your personal missed list. All local.",
    "category": "Writing & Language",
    "file": "irregular-verbs-trainer.html",
    "path": "cards/irregular-verbs-trainer.html"
  },
  {
    "id": "isbn-10-13-converter-title",
    "name": "isbn-10-13-converter",
    "title": "📚 ISBN-10 ⇄ ISBN-13 Converter",
    "description": "Validate an ISBN-10 or ISBN-13, compute the check digit, and convert between the two. Hyphens and spaces are ignored. Check digits follow the ISBN / EAN rules — this does not look up a book.",
    "category": "Algorithms & Computer Science",
    "file": "isbn-10-13-converter.html",
    "path": "cards/isbn-10-13-converter.html"
  },
  {
    "id": "iso-week-number-finder-title",
    "name": "iso-week-number-finder",
    "title": "📆 ISO Week Number Finder",
    "description": "Convert a date to its ISO-8601 week (YYYY-Www-d) and the other way around. Weeks start on Monday; week 1 is the week with 4 January (the week containing the first Thursday).",
    "category": "Productivity & Lifestyle",
    "file": "iso-week-number-finder.html",
    "path": "cards/iso-week-number-finder.html"
  },
  {
    "id": "japanese-era-nengo-title",
    "name": "japanese-era-nengo",
    "title": "🏯 The Nengō Desk",
    "description": "Japanese objects are dated in era years: Meiji 6, Shōwa 20, Reiwa 6. Year 1 of an era is the year it was proclaimed, even if that was December. The desk covers Meiji (1868) to Reiwa. Earlier nengō ...",
    "category": "Museum & Collection",
    "file": "japanese-era-nengo.html",
    "path": "cards/japanese-era-nengo.html"
  },
  {
    "id": "japanese-jlpt-vocabulary-title",
    "name": "japanese-jlpt-vocabulary",
    "title": "📖 JLPT Vocabulary Studio",
    "description": "Supercharge your Japanese vocabulary for the JLPT N5 and N4 examinations. Includes native audio pronunciation, Furigana reading toggles, English definitions, and contextual example sentences.",
    "category": "Writing & Language",
    "file": "japanese-jlpt-vocabulary.html",
    "path": "cards/japanese-jlpt-vocabulary.html"
  },
  {
    "id": "japanese-kana-trainer-title",
    "name": "japanese-kana-trainer",
    "title": "🎌 Japanese Kana Trainer",
    "description": "Master the foundation of Japanese. Interactive 46-character syllabaries for both Hiragana and Katakana with native audio pronunciation, dakuten/handakuten sound changes, and a speed flashcard drill...",
    "category": "Writing & Language",
    "file": "japanese-kana-trainer.html",
    "path": "cards/japanese-kana-trainer.html"
  },
  {
    "id": "japanese-keigo-politeness-title",
    "name": "japanese-keigo-politeness",
    "title": "👑 Japanese Keigo Master",
    "description": "Navigate the 3 crucial Japanese speech registers: Casual (with friends), Teineigo (everyday polite), Sonkeigo (honorific/clients), and Kenjougo (humble/self-lowering).",
    "category": "Writing & Language",
    "file": "japanese-keigo-politeness.html",
    "path": "cards/japanese-keigo-politeness.html"
  },
  {
    "id": "japanese-numbers-counters-title",
    "name": "japanese-numbers-counters",
    "title": "🔢 Japanese Counters & Numbers",
    "description": "Conquer Japanese counter words (助数詞 - Josūshi). In Japanese, you cannot simply say \"three beers\" or \"two cats\"—objects require specific counters with euphonic sound shifts (rendaku).",
    "category": "Writing & Language",
    "file": "japanese-numbers-counters.html",
    "path": "cards/japanese-numbers-counters.html"
  },
  {
    "id": "japanese-particles-master-title",
    "name": "japanese-particles-master",
    "title": "🧩 Japanese Particles Master",
    "description": "Master the grammatical glue of Japanese sentences (助詞 - Joshi). Practice tricky distinctions like は vs が (topic vs subject) and に vs で (time/target vs location of action) with interactive fill-in-t...",
    "category": "Writing & Language",
    "file": "japanese-particles-master.html",
    "path": "cards/japanese-particles-master.html"
  },
  {
    "id": "japanese-romaji-converter-title",
    "name": "japanese-romaji-converter",
    "title": "🔄 Romaji & Kana Converter",
    "description": "Type in standard alphabet (Romaji) and watch it convert in real-time into Hiragana and Katakana. Also translates Kana back into Hepburn Romaji with 1-click text-to-speech audio pronunciation.",
    "category": "Writing & Language",
    "file": "japanese-romaji-converter.html",
    "path": "cards/japanese-romaji-converter.html"
  },
  {
    "id": "japanese-verb-conjugator-title",
    "name": "japanese-verb-conjugator",
    "title": "⚡ Japanese Verb Conjugator",
    "description": "Instantly conjugate any Japanese verb across all core grammatical forms (Present, Negative, Past, Te-form, Potential, Volitional, and Passive) with group detection (Godan, Ichidan, Irregular).",
    "category": "Writing & Language",
    "file": "japanese-verb-conjugator.html",
    "path": "cards/japanese-verb-conjugator.html"
  },
  {
    "id": "jet-lag-sleep-shift-planner-title",
    "name": "jet-lag-sleep-shift-planner",
    "title": "✈️ Jet Lag Sleep Shift Planner",
    "description": "Plan a sleep shift for a timezone jump. Eastbound is harder (phase advance ~1 h/day); westbound is easier (~1.5 h/day). Times are a circadian rule of thumb, not a flight-medicine consult.",
    "category": "Lucid Dreaming & Sleep",
    "file": "jet-lag-sleep-shift-planner.html",
    "path": "cards/jet-lag-sleep-shift-planner.html"
  },
  {
    "id": "json-beautifier-validator-title",
    "name": "json-beautifier-validator",
    "title": "🔧 JSON Beautifier & Linter",
    "description": "Format, minify, validate, and debug JSON payloads with exact syntax error line tracking. 100% private in-browser parsing.",
    "category": "Productivity & Lifestyle",
    "file": "json-beautifier-validator.html",
    "path": "cards/json-beautifier-validator.html"
  },
  {
    "id": "json-flatten-unflatten-title",
    "name": "json-flatten-unflatten",
    "title": "🧩 JSON Flatten / Unflatten",
    "description": "Nested objects become dotted keys (user.address.city); arrays use items.0. Unflatten rebuilds the tree. Runs in this page — nothing is uploaded.",
    "category": "Algorithms & Computer Science",
    "file": "json-flatten-unflatten.html",
    "path": "cards/json-flatten-unflatten.html"
  },
  {
    "id": "json-ld-structured-data-generator-title",
    "name": "json-ld-structured-data-generator",
    "title": "🏷️ Rich Result Forge",
    "description": "Build valid schema.org JSON-LD for the rich results Google actually shows — products with price and availability, FAQs, breadcrumbs, events, local businesses, articles. Fields are validated as you ...",
    "category": "SaaS & Business Killers",
    "file": "json-ld-structured-data-generator.html",
    "path": "cards/json-ld-structured-data-generator.html"
  },
  {
    "id": "json-to-typescript-interface-generator-title",
    "name": "json-to-typescript-interface-generator",
    "title": "🧬 JSON Schema Forge",
    "description": "Paste any JSON response and get production-ready types in six dialects at once: TypeScript interfaces, a Zod schema, Python dataclasses, Go structs, C# classes and a JSON Schema document. Nested ob...",
    "category": "SaaS & Business Killers",
    "file": "json-to-typescript-interface-generator.html",
    "path": "cards/json-to-typescript-interface-generator.html"
  },
  {
    "id": "json-yaml-diff-validator-title",
    "name": "json-yaml-diff-validator",
    "title": "🔧 JSON & YAML Studio",
    "description": "Format, validate, convert between JSON & YAML, and compare structural diffs side-by-side. 100% private in-browser processing.",
    "category": "Productivity & Lifestyle",
    "file": "json-yaml-diff-validator.html",
    "path": "cards/json-yaml-diff-validator.html"
  },
  {
    "id": "julian-day-date-converter-title",
    "name": "julian-day-date-converter",
    "title": "🌌 Julian Day Converter",
    "description": "Convert a calendar date to Julian Day Number (JDN) and Modified Julian Date (MJD = JD − 2,400,000.5). Astronomers count days from noon UTC on 1 January 4713 BCE. Gregorian calendar after 15 Oct 1582.",
    "category": "Productivity & Lifestyle",
    "file": "julian-day-date-converter.html",
    "path": "cards/julian-day-date-converter.html"
  },
  {
    "id": "jwt-decoder-title",
    "name": "jwt-decoder",
    "title": "🔐 JWT Decoder & Inspector",
    "description": "Decode and inspect JSON Web Tokens. View header, payload, and signature. Check expiration, validate claims, and understand your tokens.",
    "category": "Algorithms & Computer Science",
    "file": "jwt-decoder.html",
    "path": "cards/jwt-decoder.html"
  },
  {
    "id": "jwt-token-decoder-inspector-title",
    "name": "jwt-token-decoder-inspector",
    "title": "🔑 JWT Token Inspector",
    "description": "Decode and audit JSON Web Tokens offline. Zero network calls — your security tokens never leave your browser.",
    "category": "Productivity & Lifestyle",
    "file": "jwt-token-decoder-inspector.html",
    "path": "cards/jwt-token-decoder-inspector.html"
  },
  {
    "id": "kanban-sprint-flow-board-title",
    "name": "kanban-sprint-flow-board",
    "title": "📋 Offline Kanban Sprint Board",
    "description": "Lightweight, private Kanban board with drag-and-drop cards, custom columns, priority tags, WIP counts, markdown export, and local storage auto-save.",
    "category": "Productivity & Lifestyle",
    "file": "kanban-sprint-flow-board.html",
    "path": "cards/kanban-sprint-flow-board.html"
  },
  {
    "id": "kanji-helper-title",
    "name": "kanji-helper",
    "title": "🎌 Japanese Kanji Helper",
    "description": "Learn, practice, and master Japanese kanji with REAL stroke order animations, meanings, readings, and example words.",
    "category": "Writing & Language",
    "file": "kanji-helper.html",
    "path": "cards/kanji-helper.html"
  },
  {
    "id": "karvonen-heart-rate-zones-title",
    "name": "karvonen-heart-rate-zones",
    "title": "❤️ Karvonen Heart Rate Zones",
    "description": "Target HR = ((HRmax − HRrest) × intensity) + HRrest. HRmax default is 220 − age (a rough estimate). Zones are training labels, not medical advice. Stop if you feel unwell.",
    "category": "Health & Fitness",
    "file": "karvonen-heart-rate-zones.html",
    "path": "cards/karvonen-heart-rate-zones.html"
  },
  {
    "id": "kelvin-helmholtz-cloud-instability-title",
    "name": "kelvin-helmholtz-cloud-instability",
    "title": "☁️ Kelvin-Helmholtz Waves",
    "description": "Atmospheric fluid shear-flow instability. Two fluid layers with differing densities and velocities roll up into breaking ocean-billow cloud vortices.",
    "category": "Science & Engineering",
    "file": "kelvin-helmholtz-cloud-instability.html",
    "path": "cards/kelvin-helmholtz-cloud-instability.html"
  },
  {
    "id": "keyboard-event-key-code-inspector-title",
    "name": "keyboard-event-key-code-inspector",
    "title": "⌨️ JavaScript Keyboard Event KeyCode Inspector",
    "description": "Live interactive JavaScript keyboard event inspector showing event.key, event.code, keyCode, which, modifiers, location, and ready-to-copy event listener code.",
    "category": "Algorithms & Computer Science",
    "file": "keyboard-event-key-code-inspector.html",
    "path": "cards/keyboard-event-key-code-inspector.html"
  },
  {
    "id": "keyboard-key-tester-title",
    "name": "keyboard-key-tester",
    "title": "⌨️ Keyboard Tester",
    "description": "Click the box and press keys. Shows event.key, code and modifiers — handy when a laptop key died or a layout is fighting you. Nothing is recorded.",
    "category": "Algorithms & Computer Science",
    "file": "keyboard-key-tester.html",
    "path": "cards/keyboard-key-tester.html"
  },
  {
    "id": "keyword-density-word-frequency-title",
    "name": "keyword-density-word-frequency",
    "title": "📊 Keyword Density & Word Frequency",
    "description": "Paste copy and see word count, the densest terms, and an optional target keyword’s density. Counts are local and crude (no stemming). Density is a diagnostic, not a Google ranking lever — stuffing ...",
    "category": "Writing & Language",
    "file": "keyword-density-word-frequency.html",
    "path": "cards/keyword-density-word-frequency.html"
  },
  {
    "id": "kitchen-science-experiments-title",
    "name": "kitchen-science-experiments",
    "title": "🧪 Kitchen Science Lab",
    "description": "10 safe, spectacular experiments using stuff already in your kitchen — each with step-by-step instructions, the real science explained, and safety notes. Perfect for curious kids and parents.",
    "category": "Science & Engineering",
    "file": "kitchen-science-experiments.html",
    "path": "cards/kitchen-science-experiments.html"
  },
  {
    "id": "klein-bottle-mobius-lab-title",
    "name": "klein-bottle-mobius-lab",
    "title": "🌀 Klein Bottle & Möbius Lab",
    "description": "Surfaces that shouldn't exist: a Möbius strip with adjustable twists, a Klein bottle (inside IS outside), and torus knots you design with p/q sliders. Points, wireframe or solid candy render.",
    "category": "Mathematics",
    "file": "klein-bottle-mobius-lab.html",
    "path": "cards/klein-bottle-mobius-lab.html"
  },
  {
    "id": "knots-mph-kph-converter-title",
    "name": "knots-mph-kph-converter",
    "title": "⛵ Knots ⇄ mph ⇄ km/h",
    "description": "One knot is one nautical mile per hour. A nautical mile is exactly 1,852 m, so 1 kn = 1.852 km/h ≈ 1.15078 mph. Used by ships, aircraft and marine forecasts.",
    "category": "Science & Engineering",
    "file": "knots-mph-kph-converter.html",
    "path": "cards/knots-mph-kph-converter.html"
  },
  {
    "id": "koppen-climate-classifier-title",
    "name": "koppen-climate-classifier",
    "title": "🌦️ Köppen Climate Classifier",
    "description": "Type in twelve monthly temperatures and rainfall totals and this runs the full Köppen–Geiger decision tree on them — the same classification used on every climate map — showing not just the code (C...",
    "category": "Science & Engineering",
    "file": "koppen-climate-classifier.html",
    "path": "cards/koppen-climate-classifier.html"
  },
  {
    "id": "korean-hangul-trainer-title",
    "name": "korean-hangul-trainer",
    "title": "🇰🇷 Korean Hangul Trainer",
    "description": "Learn Hangul (한글), the world's most scientific writing system. Explore the 14 basic consonants, 10 vowels, and combine them into complete Korean syllable blocks with native audio pronunciation (`ko...",
    "category": "Writing & Language",
    "file": "korean-hangul-trainer.html",
    "path": "cards/korean-hangul-trainer.html"
  },
  {
    "id": "lab-planner-title",
    "name": "lab-planner",
    "title": "Lab Planner",
    "description": "Plan lab experiments by organizing materials, steps, and timing. Enter details and generate a structured plan.",
    "category": "Science & Engineering",
    "file": "lab-planner.html",
    "path": "cards/lab-planner.html"
  },
  {
    "id": "lab-safety-title",
    "name": "lab-safety",
    "title": "Lab Safety Tools & Facts",
    "description": "Review lab safety rules and generate reminders for safe scientific work.",
    "category": "Science & Engineering",
    "file": "lab-safety.html",
    "path": "cards/lab-safety.html"
  },
  {
    "id": "laminate-flooring-calculator-title",
    "name": "laminate-flooring-calculator",
    "title": "🪵 Laminate Flooring Calculator",
    "description": "Work out how many packs of laminate to buy: enter the room, the plank size, planks per pack and pack price, and this adds the wastage so you don't run short mid-lay.",
    "category": "Home & DIY",
    "file": "laminate-flooring-calculator.html",
    "path": "cards/laminate-flooring-calculator.html"
  },
  {
    "id": "languages-title",
    "name": "languages",
    "title": "Languages Tool",
    "description": "Translate words, check meanings, and practice languages. Uses open-source translation services.",
    "category": "Writing & Language",
    "file": "languages.html",
    "path": "cards/languages.html"
  },
  {
    "id": "late-payment-interest-chaser-title",
    "name": "late-payment-interest-chaser",
    "title": "⏰ Late Payment Interest & Chaser Letter",
    "description": "Unpaid invoice? UK law lets you charge 8% above the Bank of England base rate plus fixed compensation on overdue business invoices — automatically, even if your contract never mentioned it. Calcula...",
    "category": "Finance & Money",
    "file": "late-payment-interest-chaser.html",
    "path": "cards/late-payment-interest-chaser.html"
  },
  {
    "id": "latin-date-kalends-nones-title",
    "name": "latin-date-kalends-nones",
    "title": "📜 The Kalends Desk",
    "description": "Romans counted forward to the next named day, inclusively. The named days are the Kalends (1st), the Nones (5th, or 7th in Mar/May/Jul/Oct) and the Ides (13th, or 15th in those four months). The Id...",
    "category": "Museum & Collection",
    "file": "latin-date-kalends-nones.html",
    "path": "cards/latin-date-kalends-nones.html"
  },
  {
    "id": "laundry-care-label-stain-solver-title",
    "name": "laundry-care-label-stain-solver",
    "title": "🧺 Laundry Care & Stain Solver",
    "description": "The complete &ldquo;how to actually do it&rdquo; guide: pick a fabric and get the right water, cycle and drying, get a step-by-step recipe for any stain, and decode those cryptic care-label symbols...",
    "category": "Productivity & Lifestyle",
    "file": "laundry-care-label-stain-solver.html",
    "path": "cards/laundry-care-label-stain-solver.html"
  },
  {
    "id": "laundry-title",
    "name": "laundry",
    "title": "Laundry Tracker",
    "description": "Log laundry loads, track completion, and monitor laundry habits with statistics.",
    "category": "Productivity & Lifestyle",
    "file": "laundry.html",
    "path": "cards/laundry.html"
  },
  {
    "id": "leanbodymass-title",
    "name": "leanbodymass",
    "title": "Lean Body Mass Calculator",
    "description": "Estimate your lean body mass using multiple formulas and get detailed body composition analysis.",
    "category": "Health & Fitness",
    "file": "leanbodymass.html",
    "path": "cards/leanbodymass.html"
  },
  {
    "id": "leap-year-weekday-finder-title",
    "name": "leap-year-weekday-finder",
    "title": "📆 Leap Year & Weekday",
    "description": "Gregorian leap years are divisible by 4, except centuries unless divisible by 400. 1900 was not a leap year; 2000 was. Also shows the weekday for any date your browser can represent.",
    "category": "Productivity & Lifestyle",
    "file": "leap-year-weekday-finder.html",
    "path": "cards/leap-year-weekday-finder.html"
  },
  {
    "id": "learning-style-title",
    "name": "learning-style",
    "title": "🧭 Learning Style Self-Assessment",
    "description": "Answer 8 quick questions to discover your preferred learning style: Visual, Auditory, Reading/Writing, or Kinaesthetic.",
    "category": "Productivity & Lifestyle",
    "file": "learning-style.html",
    "path": "cards/learning-style.html"
  },
  {
    "id": "lease-title",
    "name": "lease",
    "title": "🚗 Lease vs Buy Calculator",
    "description": "Compare the true cost of leasing a vehicle against buying it outright or on finance, over the same term. Accounts for deposit, monthly payments, residual value and what the car is worth at the end.",
    "category": "Finance & Money",
    "file": "lease.html",
    "path": "cards/lease.html"
  },
  {
    "id": "led-current-limiting-resistor-title",
    "name": "led-current-limiting-resistor",
    "title": "💡 LED Current-Limiting Resistor",
    "description": "R = (supply − LED Vf) / current. Typical Vf: red ~1.8–2.2 V, green/blue/white ~3.0–3.4 V. Always put a resistor in series with a bare LED on a voltage source — the LED will not self-limit.",
    "category": "Science & Engineering",
    "file": "led-current-limiting-resistor.html",
    "path": "cards/led-current-limiting-resistor.html"
  },
  {
    "id": "led-watt-equivalent-calculator-title",
    "name": "led-watt-equivalent-calculator",
    "title": "💡 LED Watt Equivalent Calculator",
    "description": "Rough incandescent, halogen and CFL wattage versus LED lumens. Packaging lumens win over “60 W equivalent” marketing. Efficacy defaults to typical household LEDs (~90 lm/W).",
    "category": "Science & Engineering",
    "file": "led-watt-equivalent-calculator.html",
    "path": "cards/led-watt-equivalent-calculator.html"
  },
  {
    "id": "lighting-design-title",
    "name": "lighting-design",
    "title": "💡 Lighting Design Calculator",
    "description": "Professional lighting design calculator with comprehensive room analysis, fixture selection, and energy efficiency recommendations. ⚠️ Educational tool — consult certified lighting designers for ac...",
    "category": "Science & Engineering",
    "file": "lighting-design.html",
    "path": "cards/lighting-design.html"
  },
  {
    "id": "linear-algebra-title",
    "name": "linear-algebra",
    "title": "Linear Algebra Helper",
    "description": "Perform comprehensive linear algebra operations with step-by-step solutions, matrix visualization, and educational explanations.",
    "category": "Mathematics",
    "file": "linear-algebra.html",
    "path": "cards/linear-algebra.html"
  },
  {
    "id": "linux-bash-builder-title",
    "name": "linux-bash-builder",
    "title": "🐚 Bash Script Builder",
    "description": "Build bash scripts from common patterns — select blocks, customize, and copy the complete script",
    "category": "Algorithms & Computer Science",
    "file": "linux-bash-builder.html",
    "path": "cards/linux-bash-builder.html"
  },
  {
    "id": "linux-chmod-calculator-title",
    "name": "linux-chmod-calculator",
    "title": "🔒 chmod Permission Calculator",
    "description": "Visually set file permissions — toggle read/write/execute for owner, group, and others. Get octal, symbolic, and the full command",
    "category": "Algorithms & Computer Science",
    "file": "linux-chmod-calculator.html",
    "path": "cards/linux-chmod-calculator.html"
  },
  {
    "id": "linux-command-cheatsheet-title",
    "name": "linux-command-cheatsheet",
    "title": "🐧 Linux Command Cheat Sheet",
    "description": "Searchable reference of 200+ Linux commands — filter by category, copy with one click",
    "category": "Algorithms & Computer Science",
    "file": "linux-command-cheatsheet.html",
    "path": "cards/linux-command-cheatsheet.html"
  },
  {
    "id": "linux-cron-builder-title",
    "name": "linux-cron-builder",
    "title": "⏰ Cron Expression Builder",
    "description": "Visually build cron schedules — see next 10 run times, get the crontab command, and browse common presets",
    "category": "Algorithms & Computer Science",
    "file": "linux-cron-builder.html",
    "path": "cards/linux-cron-builder.html"
  },
  {
    "id": "linux-disk-analyzer-title",
    "name": "linux-disk-analyzer",
    "title": "💾 Disk Space Analyzer & Planner",
    "description": "Calculate partition sizes, plan disk layouts, convert units, and get the commands to set it all up",
    "category": "Algorithms & Computer Science",
    "file": "linux-disk-analyzer.html",
    "path": "cards/linux-disk-analyzer.html"
  },
  {
    "id": "linux-log-analyzer-title",
    "name": "linux-log-analyzer",
    "title": "📋 Log Analyzer & Command Generator",
    "description": "Paste log output to get instant analysis, or generate commands to search, filter, and monitor logs",
    "category": "Algorithms & Computer Science",
    "file": "linux-log-analyzer.html",
    "path": "cards/linux-log-analyzer.html"
  },
  {
    "id": "linux-regex-tester-title",
    "name": "linux-regex-tester",
    "title": "🔍 Regex Tester & Builder",
    "description": "Test regular expressions live — see matches highlighted, capture groups extracted, and get the grep/sed/awk command",
    "category": "Algorithms & Computer Science",
    "file": "linux-regex-tester.html",
    "path": "cards/linux-regex-tester.html"
  },
  {
    "id": "linux-signal-reference-title",
    "name": "linux-signal-reference",
    "title": "📡 Linux Process & Signal Reference",
    "description": "Complete reference of Linux signals, process states, and process management commands with examples",
    "category": "Algorithms & Computer Science",
    "file": "linux-signal-reference.html",
    "path": "cards/linux-signal-reference.html"
  },
  {
    "id": "linux-ssh-generator-title",
    "name": "linux-ssh-generator",
    "title": "🔑 SSH Command Generator",
    "description": "Build SSH, SCP, and SSH tunnel commands — fill in the options, copy the command",
    "category": "Algorithms & Computer Science",
    "file": "linux-ssh-generator.html",
    "path": "cards/linux-ssh-generator.html"
  },
  {
    "id": "linux-systemd-generator-title",
    "name": "linux-systemd-generator",
    "title": "⚙️ Systemd Service Generator",
    "description": "Generate systemd .service unit files — fill in the details, get a complete service file with install instructions",
    "category": "Algorithms & Computer Science",
    "file": "linux-systemd-generator.html",
    "path": "cards/linux-systemd-generator.html"
  },
  {
    "id": "lissajous-laser-oscillograph-title",
    "name": "lissajous-laser-oscillograph",
    "title": "⚡ Lissajous Laser Projector",
    "description": "Dual-galvanometer laser projector simulating orthogonal harmonic oscillations, phase shifts, and phosphorescent persistence curves.",
    "category": "Science & Engineering",
    "file": "lissajous-laser-oscillograph.html",
    "path": "cards/lissajous-laser-oscillograph.html"
  },
  {
    "id": "literature-analysis-title",
    "name": "literature-analysis",
    "title": "🧠 AI Study Assistant",
    "description": "🚀 Ace your exams: Transform any topic into flashcards, practice quizzes, study guides, and mnemonics. Perfect for students, lifelong learners, and professionals.",
    "category": "Writing & Language",
    "file": "literature-analysis.html",
    "path": "cards/literature-analysis.html"
  },
  {
    "id": "literature-title",
    "name": "literature",
    "title": "📚 AI Literature Analyzer",
    "description": "🚀 Ultimate literary toolkit: Analyze any text AND generate study materials. Perfect for students, teachers, and book lovers.",
    "category": "Writing & Language",
    "file": "literature.html",
    "path": "cards/literature.html"
  },
  {
    "id": "llm-prompt-token-counter-title",
    "name": "llm-prompt-token-counter",
    "title": "💬 LLM Prompt Token Counter",
    "description": "Estimate LLM token usage, calculate API cost per query, and compress prompt text to eliminate token waste and latency.",
    "category": "Writing & Language",
    "file": "llm-prompt-token-counter.html",
    "path": "cards/llm-prompt-token-counter.html"
  },
  {
    "id": "load-calculator-title",
    "name": "load-calculator",
    "title": "⚡ Electrical Load Calculator",
    "description": "🔧 Professional-grade calculations: Calculate electrical loads for homes, offices, or circuits. Includes NEC compliance tips and safety warnings.",
    "category": "Science & Engineering",
    "file": "load-calculator.html",
    "path": "cards/load-calculator.html"
  },
  {
    "id": "loan-amortization-schedule-calculator-title",
    "name": "loan-amortization-schedule-calculator",
    "title": "📈 Loan & Mortgage Amortization Schedule Calculator",
    "description": "Calculate monthly loan payments, view complete annual and monthly amortization schedules, and simulate the interest savings of extra principal payments.",
    "category": "Finance & Money",
    "file": "loan-amortization-schedule-calculator.html",
    "path": "cards/loan-amortization-schedule-calculator.html"
  },
  {
    "id": "loan-amortization-schedule-title",
    "name": "loan-amortization-schedule",
    "title": "📅 Loan Amortization Schedule",
    "description": "Fixed-rate repayment loan. Payment = P × r(1+r)^n / ((1+r)^n − 1) with r = APR/12. First 24 months shown; totals cover the whole term. Not a credit decision.",
    "category": "Finance & Money",
    "file": "loan-amortization-schedule.html",
    "path": "cards/loan-amortization-schedule.html"
  },
  {
    "id": "loan-title",
    "name": "loan",
    "title": "💰 Smart Loan Calculator",
    "description": "💸 Plan your finances: Calculate mortgage, car loan, personal loan payments with amortization schedule. Compare scenarios and save thousands!",
    "category": "Finance & Money",
    "file": "loan.html",
    "path": "cards/loan.html"
  },
  {
    "id": "logarithms-title",
    "name": "logarithms",
    "title": "📉 Logarithm Calculator",
    "description": "Evaluate logarithms in any base, convert between bases, and solve for an unknown exponent. Shows the change-of-base working so you can follow it on paper.",
    "category": "Mathematics",
    "file": "logarithms.html",
    "path": "cards/logarithms.html"
  },
  {
    "id": "logic-detective-puzzle-club-title",
    "name": "logic-detective-puzzle-club",
    "title": "🕵️ Logic Detective Puzzle Club",
    "description": "8 classic logic puzzles that have stumped clever people for centuries — with progressive hints, full solutions and detective-rank progress tracking. No maths degree required.",
    "category": "Mind-Blowing Demos",
    "file": "logic-detective-puzzle-club.html",
    "path": "cards/logic-detective-puzzle-club.html"
  },
  {
    "id": "logic-gate-circuit-simulator-title",
    "name": "logic-gate-circuit-simulator",
    "title": "⚡ Logic Gate Simulator",
    "description": "Simulate fundamental boolean logic gates (AND, OR, XOR, NAND) and digital circuits with live voltage probes and dynamic truth tables.",
    "category": "Science & Engineering",
    "file": "logic-gate-circuit-simulator.html",
    "path": "cards/logic-gate-circuit-simulator.html"
  },
  {
    "id": "long-division-trainer-title",
    "name": "long-division-trainer",
    "title": "➗ Long Division Step-by-Step Trainer",
    "description": "See every step of long division — divide, multiply, subtract, bring down — then practise on a generated calculation with full remainder and check-back working. All local, nothing sent anywhere.",
    "category": "Mathematics",
    "file": "long-division-trainer.html",
    "path": "cards/long-division-trainer.html"
  },
  {
    "id": "lorem-ipsum-generator-title",
    "name": "lorem-ipsum-generator",
    "title": "📜 Lorem Ipsum Generator",
    "description": "Generate placeholder text for designs, mockups, and layouts. Choose paragraphs, sentences, or words with one click.",
    "category": "Writing & Language",
    "file": "lorem-ipsum-generator.html",
    "path": "cards/lorem-ipsum-generator.html"
  },
  {
    "id": "lorem-ipsum-placeholder-generator-title",
    "name": "lorem-ipsum-placeholder-generator",
    "title": "📝 Lorem Ipsum & Placeholder Generator",
    "description": "Generate clean dummy copy for wireframes, CMS previews, slide decks and prototypes. Pick classic lorem ipsum or readable English-style filler, choose the amount and export it as plain text, HTML or...",
    "category": "SaaS & Business Killers",
    "file": "lorem-ipsum-placeholder-generator.html",
    "path": "cards/lorem-ipsum-placeholder-generator.html"
  },
  {
    "id": "lorem-ipsum-placeholder-text-title",
    "name": "lorem-ipsum-placeholder-text",
    "title": "📄 Lorem Ipsum & Placeholder Text",
    "description": "Generate filler text for mockups and layouts: classic Lorem Ipsum, plain English, or themed flavours (tech jargon, cooking, pirate, corporate, hip hop). Choose paragraphs, sentences or words, wrap ...",
    "category": "Writing & Language",
    "file": "lorem-ipsum-placeholder-text.html",
    "path": "cards/lorem-ipsum-placeholder-text.html"
  },
  {
    "id": "lorenz-attractor-title",
    "name": "lorenz-attractor",
    "title": "🌪️ Lorenz Attractor — the Butterfly Effect",
    "description": "Three perfectly deterministic equations, zero randomness — yet the path swirls forever around two wings and never repeats. This is chaos: predictability with a built-in expiry date, the seed of the...",
    "category": "Mind-Blowing Demos",
    "file": "lorenz-attractor.html",
    "path": "cards/lorenz-attractor.html"
  },
  {
    "id": "ltv-mortgage-calculator-title",
    "name": "ltv-mortgage-calculator",
    "title": "🏦 LTV Mortgage Calculator",
    "description": "Loan-to-value = mortgage ÷ property price. UK product tiers often sit at 60, 75, 85, 90, 95%. Deposit is price − loan. Not a lender decision and not advice.",
    "category": "Finance & Money",
    "file": "ltv-mortgage-calculator.html",
    "path": "cards/ltv-mortgage-calculator.html"
  },
  {
    "id": "lucid-dream-quest-taskboard-title",
    "name": "lucid-dream-quest-taskboard",
    "title": "🎯 Lucid Dream Quest Taskboard",
    "description": "Intentional task priming board. Having a clear pre-sleep mission dramatically reinforces prospective memory once lucidity strikes, eliminating disorientation.",
    "category": "Lucid Dreaming & Sleep",
    "file": "lucid-dream-quest-taskboard.html",
    "path": "cards/lucid-dream-quest-taskboard.html"
  },
  {
    "id": "lucid-dream-stabilizer-sim-title",
    "name": "lucid-dream-stabilizer-sim",
    "title": "✨ Lucid Dream Stabilizer Lab",
    "description": "Emergency stabilization maneuvers when lucidity triggers. Overcome the premature waking reflex, dream scene fading, and false awakenings.",
    "category": "Lucid Dreaming & Sleep",
    "file": "lucid-dream-stabilizer-sim.html",
    "path": "cards/lucid-dream-stabilizer-sim.html"
  },
  {
    "id": "lucid-reality-check-trainer-title",
    "name": "lucid-reality-check-trainer",
    "title": "👁️ Lucid Reality Check Trainer",
    "description": "Condition waking critical state-testing reflexes into your subconscious. Performing 10+ intentional reality tests during the day carries directly into REM dreams.",
    "category": "Lucid Dreaming & Sleep",
    "file": "lucid-reality-check-trainer.html",
    "path": "cards/lucid-reality-check-trainer.html"
  },
  {
    "id": "lucid-supplements-timing-calc-title",
    "name": "lucid-supplements-timing-calc",
    "title": "💊 Lucid Dream Supplement Clock",
    "description": "Pharmacokinetic timing for lucid dreaming oneirogens based on LaBerge's PLOS ONE studies. Synchronizes peak Acetylcholine plasma levels ($T_{\\max}$) with late REM cycles.",
    "category": "Lucid Dreaming & Sleep",
    "file": "lucid-supplements-timing-calc.html",
    "path": "cards/lucid-supplements-timing-calc.html"
  },
  {
    "id": "luhn-check-digit-validator-title",
    "name": "luhn-check-digit-validator",
    "title": "🔢 Luhn Check Digit Validator",
    "description": "Validate or generate a Luhn (mod 10) check digit. Used by card numbers, IMEI, NPI and some barcodes. This only tests the checksum — it cannot tell you whether a number is issued, active or real.",
    "category": "Algorithms & Computer Science",
    "file": "luhn-check-digit-validator.html",
    "path": "cards/luhn-check-digit-validator.html"
  },
  {
    "id": "lumen-lux-calculator-title",
    "name": "lumen-lux-calculator",
    "title": "💡 Lumens ⇄ Lux",
    "description": "Lux = lumens ÷ area (m²) when light is spread evenly. A 800 lm bulb over a 10 m² desk is 80 lux — offices often want 300–500 lux. Beam angle and bounce are ignored.",
    "category": "Science & Engineering",
    "file": "lumen-lux-calculator.html",
    "path": "cards/lumen-lux-calculator.html"
  },
  {
    "id": "lunar-phase-illuminator-title",
    "name": "lunar-phase-illuminator",
    "title": "🌙 Lunar Phase & Illumination",
    "description": "Phase, illumination fraction, age and a drawn disc for any date and time — plus the next new and full Moons and how much moonlight is washing out the sky. Runs entirely offline.",
    "category": "Astronomy & Space",
    "file": "lunar-phase-illuminator.html",
    "path": "cards/lunar-phase-illuminator.html"
  },
  {
    "id": "lunar-tide-simulator-title",
    "name": "lunar-tide-simulator",
    "title": "🌕 Lunar Tide Simulator",
    "description": "The equilibrium tide, live: Moon and Sun each raise two opposing bulges (H ∝ cos²θ), Earth rotates beneath them, and the 24h50m lunar day makes the tide arrive 50 minutes later every day. Set the l...",
    "category": "Interactive Art & Living Worlds",
    "file": "lunar-tide-simulator.html",
    "path": "cards/lunar-tide-simulator.html"
  },
  {
    "id": "macros-title",
    "name": "macros",
    "title": "🥗 Smart Macros Calculator",
    "description": "🏋️ Achieve your goals: Calculate protein, carbs, and fats for weight loss, muscle gain, or maintenance. Get personalized meal plans and food suggestions.",
    "category": "Health & Fitness",
    "file": "macros.html",
    "path": "cards/macros.html"
  },
  {
    "id": "magnetic-eddy-current-brake-title",
    "name": "magnetic-eddy-current-brake",
    "title": "🧲 Lenz's Law Eddy Current Tube",
    "description": "Lenz's law electromagnetic braking exhibit. Drop a strong neodymium magnet down metal tubes; circulating eddy currents oppose motion, creating levitation-like terminal float.",
    "category": "Finance & Money",
    "file": "magnetic-eddy-current-brake.html",
    "path": "cards/magnetic-eddy-current-brake.html"
  },
  {
    "id": "magnetic-levitation-meissner-lab-title",
    "name": "magnetic-levitation-meissner-lab",
    "title": "🧲 Superconductor Flux Pinning",
    "description": "Type-II high-temperature superconductor cryogenic lab. Explore Meissner effect magnetic field expulsion and quantum flux pinning levitation.",
    "category": "Science & Engineering",
    "file": "magnetic-levitation-meissner-lab.html",
    "path": "cards/magnetic-levitation-meissner-lab.html"
  },
  {
    "id": "make-change-trainer-title",
    "name": "make-change-trainer",
    "title": "💰 Make Change Trainer (UK coins)",
    "description": "Work out the change from UK coins and notes, then hand the exact coins with the fewest pieces. Learn the greedy method for 1p–£2 and practise 5 rounds. Everything runs on your device.",
    "category": "Finance & Money",
    "file": "make-change-trainer.html",
    "path": "cards/make-change-trainer.html"
  },
  {
    "id": "mandelbrot-set-explorer-title",
    "name": "mandelbrot-set-explorer",
    "title": "🌀 Mandelbrot Set Explorer",
    "description": "One line — z &rarr; z&sup2; + c — repeated over and over produces infinite, self-similar complexity. Click anywhere to zoom in forever.",
    "category": "Mind-Blowing Demos",
    "file": "mandelbrot-set-explorer.html",
    "path": "cards/mandelbrot-set-explorer.html"
  },
  {
    "id": "manga-to-anime-chapter-converter-title",
    "name": "manga-to-anime-chapter-converter",
    "title": "📖 Manga to Anime Finder",
    "description": "Finished an anime season and want to continue the story? Find the exact manga chapter and volume where the anime left off, along with chapter pacing and estimated reading catch-up time.",
    "category": "Anime & Otaku Culture",
    "file": "manga-to-anime-chapter-converter.html",
    "path": "cards/manga-to-anime-chapter-converter.html"
  },
  {
    "id": "map-projection-distortion-lab-title",
    "name": "map-projection-distortion-lab",
    "title": "🗺️ Map Projection Distortion Lab",
    "description": "Every flat world map lies — the only question is how. Draw nine real projections, overlay Tissot's indicatrix (circles that show exactly how the map stretches), and get the area and angle distortio...",
    "category": "Interactive Art & Living Worlds",
    "file": "map-projection-distortion-lab.html",
    "path": "cards/map-projection-distortion-lab.html"
  },
  {
    "id": "markdown-live-editor-title",
    "name": "markdown-live-editor",
    "title": "📝 Markdown Live Editor",
    "description": "Write, preview, and format Markdown in real-time. Features instant HTML rendering, live word & reading time analytics, syntax quick-tags, and 1-click export to Markdown or HTML.",
    "category": "Writing & Language",
    "file": "markdown-live-editor.html",
    "path": "cards/markdown-live-editor.html"
  },
  {
    "id": "markdown-live-preview-title",
    "name": "markdown-live-preview",
    "title": "📝 Markdown Live Preview",
    "description": "Write Markdown on the left, see the rendered preview on the right. Supports headings, lists, code, links, images, and tables.",
    "category": "Productivity & Lifestyle",
    "file": "markdown-live-preview.html",
    "path": "cards/markdown-live-preview.html"
  },
  {
    "id": "markdown-slide-deck-builder-title",
    "name": "markdown-slide-deck-builder",
    "title": "🎞️ Deck Forge",
    "description": "Write a presentation as plain text and present it from the browser. Split slides with ---, get a live thumbnail rail, speaker notes, a run timer and full-screen mode, then export a single self-cont...",
    "category": "SaaS & Business Killers",
    "file": "markdown-slide-deck-builder.html",
    "path": "cards/markdown-slide-deck-builder.html"
  },
  {
    "id": "markdown-table-ascii-generator-title",
    "name": "markdown-table-ascii-generator",
    "title": "📊 Markdown & ASCII Table Generator",
    "description": "Interactive spreadsheet grid editor to create, format, and convert tables to GitHub-flavored Markdown, ASCII box art, Unicode borders, HTML, and CSV.",
    "category": "Algorithms & Computer Science",
    "file": "markdown-table-ascii-generator.html",
    "path": "cards/markdown-table-ascii-generator.html"
  },
  {
    "id": "markdown-table-generator-title",
    "name": "markdown-table-generator",
    "title": "▦ Markdown Table Generator",
    "description": "Paste CSV or TSV (header in row 1). Pipes in cells are escaped. Alignment is applied to every column. Copy into GitHub, Reddit or a README.",
    "category": "Algorithms & Computer Science",
    "file": "markdown-table-generator.html",
    "path": "cards/markdown-table-generator.html"
  },
  {
    "id": "markdown-to-html-printer-title",
    "name": "markdown-to-html-printer",
    "title": "📄 Markdown Document Forge",
    "description": "Transform raw Markdown into publication-ready corporate memos, academic whitepapers, and printable PDFs with 1-click browser export.",
    "category": "Writing & Language",
    "file": "markdown-to-html-printer.html",
    "path": "cards/markdown-to-html-printer.html"
  },
  {
    "id": "markup-vs-margin-calculator-title",
    "name": "markup-vs-margin-calculator",
    "title": "💹 Markup vs Margin Calculator",
    "description": "Convert cost, selling price, markup and profit margin. Markup is profit ÷ cost; margin is profit ÷ selling price. Mix them up and you under-price. Nothing is stored.",
    "category": "Finance & Money",
    "file": "markup-vs-margin-calculator.html",
    "path": "cards/markup-vs-margin-calculator.html"
  },
  {
    "id": "materials-science-title",
    "name": "materials-science",
    "title": "Materials Science Tools & Facts",
    "description": "Calculate material properties and explore fascinating facts about metals, polymers, and composites. Uses real material properties from established databases.",
    "category": "Science & Engineering",
    "file": "materials-science.html",
    "path": "cards/materials-science.html"
  },
  {
    "id": "math-practice-title",
    "name": "math-practice",
    "title": "🐚 Fibonacci & Special Sequences",
    "description": "Calculate arithmetic and geometric sequences and series. Includes step-by-step solutions and visual representations.",
    "category": "Mathematics",
    "file": "math-practice.html",
    "path": "cards/math-practice.html"
  },
  {
    "id": "math-universe-explorer-title",
    "name": "math-universe-explorer",
    "title": "🌌 Math Universe Explorer",
    "description": "Step beyond calculation into mathematical discovery. Visualize concepts, see proofs unfold, find connections humans have never seen.",
    "category": "Mathematics",
    "file": "math-universe-explorer.html",
    "path": "cards/math-universe-explorer.html"
  },
  {
    "id": "maths-flashcards-title",
    "name": "maths-flashcards",
    "title": "🧮 Maths Flashcards",
    "description": "Generate random maths flashcards for quick practice. Perfect for studying, teaching, or mental math warm-ups. 🎯 Interactive • Timed practice • Multiple topics • Progress tracking",
    "category": "Mathematics",
    "file": "maths-flashcards.html",
    "path": "cards/maths-flashcards.html"
  },
  {
    "id": "maths-title",
    "name": "maths",
    "title": "Math Helper",
    "description": "Solve mathematical expressions, equations, and practice calculations. Supports arithmetic, algebra, trigonometry, and more!",
    "category": "Mathematics",
    "file": "maths.html",
    "path": "cards/maths.html"
  },
  {
    "id": "matrices-title",
    "name": "matrices",
    "title": "Matrices Calculator",
    "description": "Perform matrix operations: addition, multiplication, determinant, inverse, transpose, and more. Supports up to 4x4 matrices with visual formatting.",
    "category": "Mathematics",
    "file": "matrices.html",
    "path": "cards/matrices.html"
  },
  {
    "id": "mattress-size-converter-title",
    "name": "mattress-size-converter",
    "title": "🛏️ Mattress Size Converter",
    "description": "UK, US and EU bed names are not the same size. A UK king is 150 × 200 cm; a US king is 193 × 203 cm. Fitted sheets do not stretch that gap. Depth (deep-fitted) is separate.",
    "category": "Home & DIY",
    "file": "mattress-size-converter.html",
    "path": "cards/mattress-size-converter.html"
  },
  {
    "id": "meal-cost-calculator-title",
    "name": "meal-cost-calculator",
    "title": "Meal Cost Calculator",
    "description": "Calculate total and per‑serving meal costs, split bills, and track ingredients. Perfect for meal planning, budgeting, and sharing costs with friends!",
    "category": "Culinary & Food Science",
    "file": "meal-cost-calculator.html",
    "path": "cards/meal-cost-calculator.html"
  },
  {
    "id": "mealplanner-title",
    "name": "mealplanner",
    "title": "Weekly Meal Planner",
    "description": "Plan your meals for the entire week, track nutrition, generate shopping lists, and save your plans. Perfect for healthy eating, budget planning, and reducing food waste!",
    "category": "Culinary & Food Science",
    "file": "mealplanner.html",
    "path": "cards/mealplanner.html"
  },
  {
    "id": "mean-arterial-pressure-calculator-title",
    "name": "mean-arterial-pressure-calculator",
    "title": "❤️ Mean Arterial Pressure",
    "description": "MAP ≈ (systolic + 2 × diastolic) / 3, plus pulse pressure. A resting MAP near 70–100 mmHg is often cited as adequate organ perfusion. This is arithmetic, not a diagnosis — chest pain or a very high...",
    "category": "Health & Fitness",
    "file": "mean-arterial-pressure-calculator.html",
    "path": "cards/mean-arterial-pressure-calculator.html"
  },
  {
    "id": "mean-median-mode-stdev-title",
    "name": "mean-median-mode-stdev",
    "title": "📊 Mean, Median, Mode & Std Dev",
    "description": "Paste numbers separated by commas, spaces or new lines. Sample standard deviation uses n − 1 (Bessel); population uses n. Mode lists every most-frequent value.",
    "category": "Mathematics",
    "file": "mean-median-mode-stdev.html",
    "path": "cards/mean-median-mode-stdev.html"
  },
  {
    "id": "mean-median-mode-trainer-title",
    "name": "mean-median-mode-trainer",
    "title": "📊 Mean, Median, Mode & Range Trainer",
    "description": "Work out the mean, median, mode and range of a data set, see the full working, and learn when each average is the right tool. 5 rounds, instant feedback, all on your device.",
    "category": "Mathematics",
    "file": "mean-median-mode-trainer.html",
    "path": "cards/mean-median-mode-trainer.html"
  },
  {
    "id": "meat-brining-salinity-calculator-title",
    "name": "meat-brining-salinity-calculator",
    "title": "🧂 Meat Brine & Cure Salinity",
    "description": "Osmotic equilibrium brining & charcuterie cure engine. Calculates exact salt weights, curing salt (Prague Powder #1) 156 PPM food safety thresholds, and time windows.",
    "category": "Culinary & Food Science",
    "file": "meat-brining-salinity-calculator.html",
    "path": "cards/meat-brining-salinity-calculator.html"
  },
  {
    "id": "meat-internal-temperature-guide-title",
    "name": "meat-internal-temperature-guide",
    "title": "🌡️ Meat Internal Temperature Guide",
    "description": "Probe the thickest part, away from bone. UK FSA safe-cook figures are listed beside common chef doneness for beef/lamb. Poultry and mince should hit the safe column. Carry-over cooking after rest c...",
    "category": "Culinary & Food Science",
    "file": "meat-internal-temperature-guide.html",
    "path": "cards/meat-internal-temperature-guide.html"
  },
  {
    "id": "meeting-bingo-title",
    "name": "meeting-bingo",
    "title": "🎯 Corporate Meeting Bingo",
    "description": "Mark off buzzwords as your colleagues say them. First to get 5 in a row wins (and loses, because you're still in the meeting).",
    "category": "Productivity & Lifestyle",
    "file": "meeting-bingo.html",
    "path": "cards/meeting-bingo.html"
  },
  {
    "id": "meeting-cost-live-ticker-title",
    "name": "meeting-cost-live-ticker",
    "title": "💸 Meeting Cost Ticker",
    "description": "Track real-time company salary burn during meetings. Keep discussions focused, respect employee time, and visualize the true cost of every minute.",
    "category": "SaaS & Business Killers",
    "file": "meeting-cost-live-ticker.html",
    "path": "cards/meeting-cost-live-ticker.html"
  },
  {
    "id": "meeting-overlap-timezone-planner-title",
    "name": "meeting-overlap-timezone-planner",
    "title": "🕒 Meeting Overlap Planner",
    "description": "Find hours when two or three cities are all awake. Uses IANA time zones and this device’s DST tables — no calendar is connected, nothing is booked.",
    "category": "Productivity & Lifestyle",
    "file": "meeting-overlap-timezone-planner.html",
    "path": "cards/meeting-overlap-timezone-planner.html"
  },
  {
    "id": "meeting-time-zone-planner-title",
    "name": "meeting-time-zone-planner",
    "title": "🌍 World Meeting Time Zone Planner",
    "description": "Find a meeting slot that works across cities. Add up to eight time zones, drag the slider through the day and see each city's local time colour-coded as working hours, early/late, or asleep. Daylig...",
    "category": "Productivity & Lifestyle",
    "file": "meeting-time-zone-planner.html",
    "path": "cards/meeting-time-zone-planner.html"
  },
  {
    "id": "meetingplanner-title",
    "name": "meetingplanner",
    "title": "Meeting Planner & Scheduler",
    "description": "Find optimal meeting times across multiple time zones, track availability, and generate meeting agendas. Perfect for remote teams, interviews, and collaborative scheduling!",
    "category": "Productivity & Lifestyle",
    "file": "meetingplanner.html",
    "path": "cards/meetingplanner.html"
  },
  {
    "id": "melting-point-finder-title",
    "name": "melting-point-finder",
    "title": "🔥 Melting Point Explorer",
    "description": "Explore melting points of hundreds of substances. Compare materials, convert units, and learn about phase changes.",
    "category": "Science & Engineering",
    "file": "melting-point-finder.html",
    "path": "cards/melting-point-finder.html"
  },
  {
    "id": "meme-translation-title",
    "name": "meme-translation",
    "title": "🎭 Meme Translator",
    "description": "The ultimate internet language decoder. Translate memes, slang, acronyms, and internet speak with context, origins, and examples. 🌐 Real-time translation across internet cultures",
    "category": "Writing & Language",
    "file": "meme-translation.html",
    "path": "cards/meme-translation.html"
  },
  {
    "id": "memento-mori-life-ticker-title",
    "name": "memento-mori-life-ticker",
    "title": "⏳ Memento Mori Life Ticker",
    "description": "Your life, visualised as a grid of weeks — then converted into how many summers, books and Sunday roasts you have left. Not to scare you. To make the next one count.",
    "category": "Productivity & Lifestyle",
    "file": "memento-mori-life-ticker.html",
    "path": "cards/memento-mori-life-ticker.html"
  },
  {
    "id": "memorization-title",
    "name": "memorization",
    "title": "🎯 Memorization Helper",
    "description": "Add items to memorize, then test yourself by revealing them later. Perfect for studying, learning vocabulary, or remembering important facts. 💡 Click items to hide/reveal • Drag to reorder • Expor...",
    "category": "Productivity & Lifestyle",
    "file": "memorization.html",
    "path": "cards/memorization.html"
  },
  {
    "id": "memory-palace-loci-builder-title",
    "name": "memory-palace-loci-builder",
    "title": "🏛️ Memory Palace Builder",
    "description": "Memorise anything with the 2,500-year-old method of loci used by memory champions. Build rooms, place vivid images at each stop, walk your palace, then test your recall.",
    "category": "Productivity & Lifestyle",
    "file": "memory-palace-loci-builder.html",
    "path": "cards/memory-palace-loci-builder.html"
  },
  {
    "id": "mental-math-sprint-trainer-title",
    "name": "mental-math-sprint-trainer",
    "title": "🧮 Mental-Math Sprint",
    "description": "A 60-second arithmetic workout with three difficulty levels, streak bonuses and a review of every question you missed. Sharpens everyday number sense — tips, change, discounts.",
    "category": "Mathematics",
    "file": "mental-math-sprint-trainer.html",
    "path": "cards/mental-math-sprint-trainer.html"
  },
  {
    "id": "messier-catalogue-hall-title",
    "name": "messier-catalogue-hall",
    "title": "🌌 The Messier Gallery",
    "description": "Charles Messier was hunting comets. These 110 smudges kept fooling him, so he numbered them (1771–81). The hall is now a rite of passage for amateur astronomers. Magnitudes are visual; distances ar...",
    "category": "Astronomy & Space",
    "file": "messier-catalogue-hall.html",
    "path": "cards/messier-catalogue-hall.html"
  },
  {
    "id": "metabolicage-title",
    "name": "metabolicage",
    "title": "⚡ Metabolic Age Estimator",
    "description": "Estimate your metabolic age based on your Basal Metabolic Rate (BMR) compared to population averages. 💡 Lower metabolic age indicates better metabolic health",
    "category": "Health & Fitness",
    "file": "metabolicage.html",
    "path": "cards/metabolicage.html"
  },
  {
    "id": "meteor-shower-sky-lab-title",
    "name": "meteor-shower-sky-lab",
    "title": "☄️ Meteor Shower Sky Lab",
    "description": "Stargaze a live meteor shower: pick a real shower (Perseids, Geminids, Leonids…), set radiant altitude, observing skill and light pollution — the model converts the catalogue Zenithal Hourly Rate i...",
    "category": "Interactive Art & Living Worlds",
    "file": "meteor-shower-sky-lab.html",
    "path": "cards/meteor-shower-sky-lab.html"
  },
  {
    "id": "metronome-title",
    "name": "metronome",
    "title": "🎵 Professional Metronome",
    "description": "Precise audible & visual metronome with subdivisions, tap tempo, and tempo presets. ⚠️ Enable sound in your browser",
    "category": "Music & Audio",
    "file": "metronome.html",
    "path": "cards/metronome.html"
  },
  {
    "id": "microbiology-title",
    "name": "microbiology",
    "title": "🔬 Microbiology Tools & Facts",
    "description": "Calculate essential microbiology values and explore fascinating facts about the invisible world of microbes. 🧫 Growth rates • Dilutions • Microbial facts • Educational insights",
    "category": "Science & Engineering",
    "file": "microbiology.html",
    "path": "cards/microbiology.html"
  },
  {
    "id": "mild-mnemonic-mantra-engine-title",
    "name": "mild-mnemonic-mantra-engine",
    "title": "🧠 MILD Lucid Dream Mantra Lab",
    "description": "Mnemonic Induction of Lucid Dreams (Stanford / Dr. Stephen LaBerge). Primes prospective memory to recognize the dream state right before entering REM sleep.",
    "category": "Lucid Dreaming & Sleep",
    "file": "mild-mnemonic-mantra-engine.html",
    "path": "cards/mild-mnemonic-mantra-engine.html"
  },
  {
    "id": "mime-type-lookup-table-title",
    "name": "mime-type-lookup-table",
    "title": "📎 MIME Type Lookup",
    "description": "Convert a file extension to a MIME type, or a MIME type back to common extensions. Handy when writing Content-Type headers, nginx maps or <input accept> lists. Lookup is local.",
    "category": "Algorithms & Computer Science",
    "file": "mime-type-lookup-table.html",
    "path": "cards/mime-type-lookup-table.html"
  },
  {
    "id": "miter-bevel-angle-calculator-title",
    "name": "miter-bevel-angle-calculator",
    "title": "📐 Miter & Bevel Angle Calculator",
    "description": "Set the saw for a perfect corner: enter the corner angle and pick flat or crown molding, and get the miter and bevel angles to dial in.",
    "category": "Home & DIY",
    "file": "miter-bevel-angle-calculator.html",
    "path": "cards/miter-bevel-angle-calculator.html"
  },
  {
    "id": "mock-data-generator-title",
    "name": "mock-data-generator",
    "title": "🧪 Mock Data Generator",
    "description": "Create repeatable sample customer, product or analytics-event datasets as JSON, CSV or SQL inserts. Names and example.test emails are deliberately fictional, so you can prototype safely without upl...",
    "category": "SaaS & Business Killers",
    "file": "mock-data-generator.html",
    "path": "cards/mock-data-generator.html"
  },
  {
    "id": "mohs-hardness-gallery-title",
    "name": "mohs-hardness-gallery",
    "title": "💎 The Mohs Gallery",
    "description": "Friedrich Mohs, 1812: a mineral of higher number scratches one of lower number. The steps are not equal — corundum to diamond is a canyon. Pick two specimens (or a thumbnail and a steel file) and t...",
    "category": "Museum & Collection",
    "file": "mohs-hardness-gallery.html",
    "path": "cards/mohs-hardness-gallery.html"
  },
  {
    "id": "moire-interference-lattice-title",
    "name": "moire-interference-lattice",
    "title": "〰️ Moiré Optical Interference",
    "description": "Kinetic optical interference exhibit. Overlay geometric optical gratings and rotate them to observe emergent macro-scale moiré superlattices.",
    "category": "Science & Engineering",
    "file": "moire-interference-lattice.html",
    "path": "cards/moire-interference-lattice.html"
  },
  {
    "id": "moisture-capillary-simulator-title",
    "name": "moisture-capillary-simulator",
    "title": "🧪 The Moisture Lab",
    "description": "Watch water migrate through building materials via capillary action — the same force that makes a sponge soak up water and makes your walls draw moisture from the ground. See why rising damp happen...",
    "category": "Museum & Collection",
    "file": "moisture-capillary-simulator.html",
    "path": "cards/moisture-capillary-simulator.html"
  },
  {
    "id": "molecule-3d-viewer-title",
    "name": "molecule-3d-viewer",
    "title": "⚛️ Molecule 3D Viewer",
    "description": "Eleven molecules and crystals as true ball-and-stick 3D — from water to a salt lattice to a diamond unit cell. Bonds are detected automatically from atomic distances, double/triple bonds included. ...",
    "category": "Science & Engineering",
    "file": "molecule-3d-viewer.html",
    "path": "cards/molecule-3d-viewer.html"
  },
  {
    "id": "monte-carlo-pi-estimator-title",
    "name": "monte-carlo-pi-estimator",
    "title": "🎯 Monte Carlo π Estimator",
    "description": "Watch &pi; emerge from pure chance: random points rain on a square with a circle inside, and the ratio that lands in the circle is exactly &pi;/4. No formula — just probability converging on a univ...",
    "category": "Mind-Blowing Demos",
    "file": "monte-carlo-pi-estimator.html",
    "path": "cards/monte-carlo-pi-estimator.html"
  },
  {
    "id": "moon-phases-eclipse-geometry-title",
    "name": "moon-phases-eclipse-geometry",
    "title": "🌘 Moon Phases & Eclipse Geometry",
    "description": "Why do phases exist, and why are eclipses so rare? Spin the Moon around Earth (its real orbital inclination is 5.14°) and rotate the line of nodes — the place where the Moon's tilted orbit crosses ...",
    "category": "Astronomy & Space",
    "file": "moon-phases-eclipse-geometry.html",
    "path": "cards/moon-phases-eclipse-geometry.html"
  },
  {
    "id": "morse-code-translator-title",
    "name": "morse-code-translator",
    "title": "📡 Morse Code Translator",
    "description": "Translate text to Morse code and back. Listen to the Morse code audio and learn the international standard.",
    "category": "Writing & Language",
    "file": "morse-code-translator.html",
    "path": "cards/morse-code-translator.html"
  },
  {
    "id": "mortgage-overpayment-calculator-title",
    "name": "mortgage-overpayment-calculator",
    "title": "🏦 Mortgage Overpayment Calculator",
    "description": "See how overpaying cuts your mortgage term and total interest. Add a monthly overpayment, a lump sum, or both, and compare against paying the normal schedule. Full amortisation worked out on your d...",
    "category": "Finance & Money",
    "file": "mortgage-overpayment-calculator.html",
    "path": "cards/mortgage-overpayment-calculator.html"
  },
  {
    "id": "mortgage-title",
    "name": "mortgage",
    "title": "🏠 Mortgage Calculator",
    "description": "Calculate detailed mortgage payments with amortization schedules, extra payments analysis, and regional comparisons. 💰 Monthly payments • Total interest • Payoff time • Amortization schedule • Reg...",
    "category": "Finance & Money",
    "file": "mortgage.html",
    "path": "cards/mortgage.html"
  },
  {
    "id": "motor-startup-title",
    "name": "motor-startup",
    "title": "⚡ Motor Startup Calculator",
    "description": "Calculate motor running/starting currents, cable sizing, protection devices, and voltage drop analysis for electrical installations. 🔧 Running current • Starting current • Cable sizing • Protectio...",
    "category": "Science & Engineering",
    "file": "motor-startup.html",
    "path": "cards/motor-startup.html"
  },
  {
    "id": "motorsport-lap-time-stint-calculator-title",
    "name": "motorsport-lap-time-stint-calculator",
    "title": "🏎️ Motorsport Lap Time & Stint Calculator",
    "description": "Turn a lap time into an average speed and a full race duration, see how much each pit stop costs, and — if you have a rival's lap time — watch the gap grow lap by lap.",
    "category": "Sports",
    "file": "motorsport-lap-time-stint-calculator.html",
    "path": "cards/motorsport-lap-time-stint-calculator.html"
  },
  {
    "id": "moving-title",
    "name": "moving",
    "title": "🚚 Ultimate Moving Planner",
    "description": "Complete moving organization tool: Create checklists, track inventory, manage budget, schedule tasks, and coordinate with family/friends. Make your move stress-free!",
    "category": "Productivity & Lifestyle",
    "file": "moving.html",
    "path": "cards/moving.html"
  },
  {
    "id": "mrprophecy-beat-memory-title",
    "name": "mrprophecy-beat-memory",
    "title": "🧠 MrProphecy: Beat Memory",
    "description": "Simon-style pad memory that grows by one step each round, scored over real MrProphecy tracks. Audio starts with the game.",
    "category": "MrProphecy Arcade",
    "file": "mrprophecy-beat-memory.html",
    "path": "cards/mrprophecy-beat-memory.html"
  },
  {
    "id": "mrprophecy-beat-runner-title",
    "name": "mrprophecy-beat-runner",
    "title": "🏃 MrProphecy: Beat Runner",
    "description": "Endless runner starring MrProphecy. Jump the gaps, build speed, and the soundtrack is real MrProphecy tracks — playback only begins when you hit start.",
    "category": "MrProphecy Arcade",
    "file": "mrprophecy-beat-runner.html",
    "path": "cards/mrprophecy-beat-runner.html"
  },
  {
    "id": "mrprophecy-crowd-surf-title",
    "name": "mrprophecy-crowd-surf",
    "title": "🤘 MrProphecy: Crowd Surf",
    "description": "Ride the crowd, collect gold notes and dodge flying drinks. Three lives, endless festival. Real MrProphecy tracks start with the game.",
    "category": "MrProphecy Arcade",
    "file": "mrprophecy-crowd-surf.html",
    "path": "cards/mrprophecy-crowd-surf.html"
  },
  {
    "id": "mrprophecy-lyric-scramble-title",
    "name": "mrprophecy-lyric-scramble",
    "title": "🔤 MrProphecy: Title Scramble",
    "description": "Unscramble real MrProphecy track titles against a sixty-second clock. Music kicks in on start, not before.",
    "category": "MrProphecy Arcade",
    "file": "mrprophecy-lyric-scramble.html",
    "path": "cards/mrprophecy-lyric-scramble.html"
  },
  {
    "id": "mrprophecy-mix-board-title",
    "name": "mrprophecy-mix-board",
    "title": "🎛️ MrProphecy: Mix Board Challenge",
    "description": "Five faders, five rounds, shrinking tolerance. Hit the target mix from the written cue. Real MrProphecy tracks run on the desk.",
    "category": "MrProphecy Arcade",
    "file": "mrprophecy-mix-board.html",
    "path": "cards/mrprophecy-mix-board.html"
  },
  {
    "id": "mrprophecy-name-that-track-title",
    "name": "mrprophecy-name-that-track",
    "title": "🎧 MrProphecy: Name That Track",
    "description": "A real MrProphecy track plays from a random point — pick the title from four options. Ten rounds, no audio until you press start.",
    "category": "MrProphecy Arcade",
    "file": "mrprophecy-name-that-track.html",
    "path": "cards/mrprophecy-name-that-track.html"
  },
  {
    "id": "mrprophecy-rhythm-tap-title",
    "name": "mrprophecy-rhythm-tap",
    "title": "🥁 MrProphecy: Rhythm Tap",
    "description": "Four-lane rhythm game scored on timing and combo, running over real MrProphecy tracks. Nothing plays until you start.",
    "category": "MrProphecy Arcade",
    "file": "mrprophecy-rhythm-tap.html",
    "path": "cards/mrprophecy-rhythm-tap.html"
  },
  {
    "id": "mrprophecy-studio-defender-title",
    "name": "mrprophecy-studio-defender",
    "title": "🛡️ MrProphecy: Studio Defender",
    "description": "Bad takes rain down on the studio — pop them before they land. Waves get faster. Real MrProphecy tracks play once you start.",
    "category": "MrProphecy Arcade",
    "file": "mrprophecy-studio-defender.html",
    "path": "cards/mrprophecy-studio-defender.html"
  },
  {
    "id": "mrprophecy-tour-manager-title",
    "name": "mrprophecy-tour-manager",
    "title": "🗺️ MrProphecy: Tour Manager",
    "description": "Twelve weeks to take MrProphecy from a Luton bedroom to a headline slot. Balance fans, cash and energy. Real tracks play while you decide.",
    "category": "MrProphecy Arcade",
    "file": "mrprophecy-tour-manager.html",
    "path": "cards/mrprophecy-tour-manager.html"
  },
  {
    "id": "mrprophecy-vinyl-catch-title",
    "name": "mrprophecy-vinyl-catch",
    "title": "💿 MrProphecy: Vinyl Catch",
    "description": "Catch falling records in the crate and dodge the cracked ones. Eight misses and the set is over. Real MrProphecy tracks play from the off.",
    "category": "MrProphecy Arcade",
    "file": "mrprophecy-vinyl-catch.html",
    "path": "cards/mrprophecy-vinyl-catch.html"
  },
  {
    "id": "mulch-coverage-calculator-title",
    "name": "mulch-coverage-calculator",
    "title": "🍂 Mulch Coverage Calculator",
    "description": "Volume = area × depth. A 50 litre bag is 0.05 m³. Bark mulch is usually 5–8 cm; paths can be 10 cm. Order a little extra for settling — bags are sold by loose volume.",
    "category": "Home & DIY",
    "file": "mulch-coverage-calculator.html",
    "path": "cards/mulch-coverage-calculator.html"
  },
  {
    "id": "multilingual-phrase-matrix-title",
    "name": "multilingual-phrase-matrix",
    "title": "🌐 10-Language Phrasebook",
    "description": "Compare, learn, and pronounce essential survival phrases side-by-side across 10 of the world's most spoken languages with instant native audio speech synthesis.",
    "category": "Writing & Language",
    "file": "multilingual-phrase-matrix.html",
    "path": "cards/multilingual-phrase-matrix.html"
  },
  {
    "id": "museum-tombstone-label-title",
    "name": "museum-tombstone-label",
    "title": "🏷️ The Tombstone Desk",
    "description": "The quiet rectangle beside the object. In Anglo-American practice: maker, dates, title in italics, date of work, medium, dimensions, credit line, accession number. Fill the fields; the wall card se...",
    "category": "Museum & Collection",
    "file": "museum-tombstone-label.html",
    "path": "cards/museum-tombstone-label.html"
  },
  {
    "id": "music-quiz-title",
    "name": "music-quiz",
    "title": "🎵 Ultimate Music Quiz",
    "description": "Interactive music knowledge challenge: Test your expertise across theory, history, instruments, and pop culture. Complete with scoring, explanations, and shareable results!",
    "category": "Music & Audio",
    "file": "music-quiz.html",
    "path": "cards/music-quiz.html"
  },
  {
    "id": "music-theory-title",
    "name": "music-theory",
    "title": "🎼 Circle of Fifths Explorer",
    "description": "Pick any key to see its relative minor, the closely related keys either side of it on the circle, and the seven diatonic chords built from that scale. Everything runs offline in the browser.",
    "category": "Music & Audio",
    "file": "music-theory.html",
    "path": "cards/music-theory.html"
  },
  {
    "id": "nanoid-generator-title",
    "name": "nanoid-generator",
    "title": "🪪 Nano ID Generator",
    "description": "URL-safe IDs from crypto.getRandomValues. Default alphabet is A–Za–z0–9_- (64 symbols). Collision odds are about (n²) / (2 × 64^size) for n IDs — this is not a password manager.",
    "category": "Algorithms & Computer Science",
    "file": "nanoid-generator.html",
    "path": "cards/nanoid-generator.html"
  },
  {
    "id": "nato-phonetic-alphabet-trainer-title",
    "name": "nato-phonetic-alphabet-trainer",
    "title": "📡 NATO Phonetic Alphabet Trainer",
    "description": "Master the international radio alphabet — Alfa, Bravo, Charlie — used so letters can never be misheard. Spell words out loud, test yourself letter by letter, and see the pronunciation table. Runs e...",
    "category": "Writing & Language",
    "file": "nato-phonetic-alphabet-trainer.html",
    "path": "cards/nato-phonetic-alphabet-trainer.html"
  },
  {
    "id": "nato-phonetic-speller-title",
    "name": "nato-phonetic-speller",
    "title": "📡 NATO Phonetic Speller",
    "description": "Spell a name, postcode or booking reference the way air-traffic and support desks do. ICAO/NATO alphabet (Alfa, Bravo…). Digits stay as words.",
    "category": "Writing & Language",
    "file": "nato-phonetic-speller.html",
    "path": "cards/nato-phonetic-speller.html"
  },
  {
    "id": "natural-electrolyte-tonic-calc-title",
    "name": "natural-electrolyte-tonic-calc",
    "title": "⚡ Natural Electrolyte Tonic Lab",
    "description": "Formulate whole-food isotonic rehydration elixirs matching World Health Organization (WHO) cellular osmolarity standards (245 mOsm/L) for sickness recovery, fevers, and intense heat.",
    "category": "Natural Remedies & Herbs",
    "file": "natural-electrolyte-tonic-calc.html",
    "path": "cards/natural-electrolyte-tonic-calc.html"
  },
  {
    "id": "nature-id-trainer-title",
    "name": "nature-id-trainer",
    "title": "🍄 Nature ID Trainer",
    "description": "Learn to spot 24 common UK/European plants and fungi from the features that actually matter in the field — leaf shape, flower colour, stem, habitat, season and a safety-relevant lookalike. Three mo...",
    "category": "Science & Engineering",
    "file": "nature-id-trainer.html",
    "path": "cards/nature-id-trainer.html"
  },
  {
    "id": "nd-filter-exposure-calculator-title",
    "name": "nd-filter-exposure-calculator",
    "title": "🕶️ ND Filter Exposure",
    "description": "New shutter = old shutter × 2^(stops). ND8 is 3 stops, ND64 is 6, ND1000 is 10. Use it for silky water and daytime video at 180° shutter. Recheck highlights — filters are not perfectly even.",
    "category": "Productivity & Lifestyle",
    "file": "nd-filter-exposure-calculator.html",
    "path": "cards/nd-filter-exposure-calculator.html"
  },
  {
    "id": "nda-contract-service-agreement-builder-title",
    "name": "nda-contract-service-agreement-builder",
    "title": "⚖️ Contract & NDA Builder",
    "description": "Generate legally-binding Non-Disclosure Agreements (NDA) and Independent Contractor Service Agreements. Customize IP assignment, confidentiality duration, non-solicitation, and jurisdiction with ze...",
    "category": "SaaS & Business Killers",
    "file": "nda-contract-service-agreement-builder.html",
    "path": "cards/nda-contract-service-agreement-builder.html"
  },
  {
    "id": "netball-scorekeeper-title",
    "name": "netball-scorekeeper",
    "title": "🏐 Netball Scorekeeper",
    "description": "Four quarters, one point a goal. Tap a team to add their goals, advance the quarter, and keep a clean running score with the per-quarter breakdown.",
    "category": "Sports",
    "file": "netball-scorekeeper.html",
    "path": "cards/netball-scorekeeper.html"
  },
  {
    "id": "networth-title",
    "name": "networth",
    "title": "💰 Personal Finance Dashboard",
    "description": "Complete personal finance dashboard: Track net worth, analyze assets vs liabilities, set financial goals, project future growth, and monitor your journey to financial freedom.",
    "category": "Finance & Money",
    "file": "networth.html",
    "path": "cards/networth.html"
  },
  {
    "id": "neural-network-playground-title",
    "name": "neural-network-playground",
    "title": "🧠 Neural Network Playground",
    "description": "Watch a tiny neural network learn XOR — the task that killed the first wave of neural networks, because a straight line can't separate the points. As it trains, the decision boundary curls into a c...",
    "category": "Algorithms & Computer Science",
    "file": "neural-network-playground.html",
    "path": "cards/neural-network-playground.html"
  },
  {
    "id": "newton-cradle-momentum-mesh-title",
    "name": "newton-cradle-momentum-mesh",
    "title": "⚪ Kinetic Momentum Cradle",
    "description": "Conservation of momentum and kinetic energy exhibit. Demonstrates compressive acoustic stress wave transmission across elastic collision chains.",
    "category": "Science & Engineering",
    "file": "newton-cradle-momentum-mesh.html",
    "path": "cards/newton-cradle-momentum-mesh.html"
  },
  {
    "id": "nginx-redirect-generator-title",
    "name": "nginx-redirect-generator",
    "title": "🔀 Nginx Redirect Generator",
    "description": "Build return / rewrite snippets for 301/302, HTTP→HTTPS and www/apex. Paste into a server { } block. A looping redirect takes a site down — test with nginx -t.",
    "category": "Algorithms & Computer Science",
    "file": "nginx-redirect-generator.html",
    "path": "cards/nginx-redirect-generator.html"
  },
  {
    "id": "note-frequency-calculator-title",
    "name": "note-frequency-calculator",
    "title": "🎹 Note Frequency Calculator",
    "description": "12-tone equal temperament: f = f₀ × 2^(n/12). Default A4 = 440 Hz. MIDI note 69 is A4. Period = 1/f.",
    "category": "Music & Audio",
    "file": "note-frequency-calculator.html",
    "path": "cards/note-frequency-calculator.html"
  },
  {
    "id": "notice-period-end-date-calculator-title",
    "name": "notice-period-end-date-calculator",
    "title": "📅 Notice Period End Date",
    "description": "Add weeks or months to the day you hand in notice. UK statutory minimums are 1 week after a month’s service and 1 week per year after two years (capped at 12) — contracts are often longer. This is ...",
    "category": "Finance & Money",
    "file": "notice-period-end-date-calculator.html",
    "path": "cards/notice-period-end-date-calculator.html"
  },
  {
    "id": "number-base-converter-title",
    "name": "number-base-converter",
    "title": "🔢 Number Base Converter",
    "description": "Convert numbers between binary, octal, decimal, hexadecimal, and any base from 2 to 36. Live conversion as you type.",
    "category": "Algorithms & Computer Science",
    "file": "number-base-converter.html",
    "path": "cards/number-base-converter.html"
  },
  {
    "id": "number-theory-title",
    "name": "number-theory",
    "title": "🧮 Advanced Number Theory Toolkit",
    "description": "Comprehensive number theory laboratory: Explore prime numbers, factorization, modular arithmetic, sequences, and advanced mathematical properties. Perfect for students, educators, cryptography enth...",
    "category": "Mathematics",
    "file": "number-theory.html",
    "path": "cards/number-theory.html"
  },
  {
    "id": "number-to-words-cheque-writer-title",
    "name": "number-to-words-cheque-writer",
    "title": "✍️ Number to Words (Cheque Writer)",
    "description": "Spell out a number in British or American English, including the cheque / check form with fractional currency. Handles values from 0 to 999,999,999,999.99. Nothing is sent off this device.",
    "category": "Finance & Money",
    "file": "number-to-words-cheque-writer.html",
    "path": "cards/number-to-words-cheque-writer.html"
  },
  {
    "id": "ohms-law-title",
    "name": "ohms-law",
    "title": "⚡ Ohm's Law Calculator",
    "description": "Instant voltage, current, resistance, and power calculations.",
    "category": "Science & Engineering",
    "file": "ohms-law.html",
    "path": "cards/ohms-law.html"
  },
  {
    "id": "onerepmax-title",
    "name": "onerepmax",
    "title": "🏋️ One-Rep Max Calculator",
    "description": "Instantly estimate your maximum lifting capacity across multiple formulas.",
    "category": "Health & Fitness",
    "file": "onerepmax.html",
    "path": "cards/onerepmax.html"
  },
  {
    "id": "optical-soliton-wave-tank-title",
    "name": "optical-soliton-wave-tank",
    "title": "🌊 Soliton Wave Flume Tank",
    "description": "John Scott Russell's 1834 hydrodynamic flume exhibit. Simulates the Korteweg–de Vries (KdV) equation where nonlinear steepening balances dispersion to form permanent solitons.",
    "category": "Science & Engineering",
    "file": "optical-soliton-wave-tank.html",
    "path": "cards/optical-soliton-wave-tank.html"
  },
  {
    "id": "optics-title",
    "name": "optics",
    "title": "🔬 Optics Calculator & Explorer",
    "description": "Calculate optical properties, simulate light behavior, and explore fascinating physics of light.",
    "category": "Science & Engineering",
    "file": "optics.html",
    "path": "cards/optics.html"
  },
  {
    "id": "optomechanical-laser-tweezer-title",
    "name": "optomechanical-laser-tweezer",
    "title": "🔬 Optical Tweezers & Trapping",
    "description": "Arthur Ashkin's 2018 Nobel Prize optical trap. Focused Gaussian laser beam gradient forces trap micro-particles and counter thermal Brownian diffusion.",
    "category": "Science & Engineering",
    "file": "optomechanical-laser-tweezer.html",
    "path": "cards/optomechanical-laser-tweezer.html"
  },
  {
    "id": "orbital-mechanics-calculator-title",
    "name": "orbital-mechanics-calculator",
    "title": "🛰️ Orbital Mechanics Lab",
    "description": "Calculate orbital velocity, Keplerian period, and gravitational escape speed around celestial bodies. Analyze Low Earth Orbit, GPS altitudes, and Geostationary synchronization.",
    "category": "Science & Engineering",
    "file": "orbital-mechanics-calculator.html",
    "path": "cards/orbital-mechanics-calculator.html"
  },
  {
    "id": "orbital-mechanics-playground-title",
    "name": "orbital-mechanics-playground",
    "title": "🚀 Orbital Mechanics Playground",
    "description": "Fly a probe through a real gravity field. Set your starting speed and direction, hit Launch, and watch the trajectory obey Newton's law (a = −GM/r², integrated semi-implicitly). Get a circle at cir...",
    "category": "Astronomy & Space",
    "file": "orbital-mechanics-playground.html",
    "path": "cards/orbital-mechanics-playground.html"
  },
  {
    "id": "order-of-operations-bodmas-trainer-title",
    "name": "order-of-operations-bodmas-trainer",
    "title": "🧠 BODMAS Step-by-Step Trainer",
    "description": "Type any expression and see it solved one operation at a time with the reason for each step — no calculator tricks, no guessing. Then take the 5-question practice round with worked solutions. Every...",
    "category": "Mathematics",
    "file": "order-of-operations-bodmas-trainer.html",
    "path": "cards/order-of-operations-bodmas-trainer.html"
  },
  {
    "id": "oscilloscope-title",
    "name": "oscilloscope",
    "title": "📡 Oscilloscope Visualizer",
    "description": "Visualize and analyze waveforms in real-time. Generate signals, adjust parameters, and explore waveforms.",
    "category": "Science & Engineering",
    "file": "oscilloscope.html",
    "path": "cards/oscilloscope.html"
  },
  {
    "id": "oven-gas-mark-temperature-converter-title",
    "name": "oven-gas-mark-temperature-converter",
    "title": "🔥 Oven Gas Mark Converter",
    "description": "Convert British gas marks to °C, °F and a typical fan/convection setting. Gas mark 4 is a moderate 180°C / 350°F oven. Fan ovens usually run about 20°C cooler than the recipe’s conventional figure.",
    "category": "Culinary & Food Science",
    "file": "oven-gas-mark-temperature-converter.html",
    "path": "cards/oven-gas-mark-temperature-converter.html"
  },
  {
    "id": "overnight-shift-duration-calculator-title",
    "name": "overnight-shift-duration-calculator",
    "title": "🌙 Overnight Shift Duration",
    "description": "Work out how long a shift is when it crosses midnight, plus unpaid breaks and overtime after a threshold. Built for night staff, on-call rotas and timesheets — not a payroll system.",
    "category": "Productivity & Lifestyle",
    "file": "overnight-shift-duration-calculator.html",
    "path": "cards/overnight-shift-duration-calculator.html"
  },
  {
    "id": "overthinkers-calculator-title",
    "name": "overthinkers-calculator",
    "title": "🧮 The Overthinker's Calculator",
    "description": "Calculate exactly how many ways a situation can go wrong. Spoiler: it's more than you think.",
    "category": "Productivity & Lifestyle",
    "file": "overthinkers-calculator.html",
    "path": "cards/overthinkers-calculator.html"
  },
  {
    "id": "overtime-pay-calculator-title",
    "name": "overtime-pay-calculator",
    "title": "⏱️ Overtime Pay Calculator",
    "description": "Split a week into regular hours and overtime at time-and-a-half, double time or a custom multiplier. Gross figures only — your contract and local labour rules still apply.",
    "category": "Finance & Money",
    "file": "overtime-pay-calculator.html",
    "path": "cards/overtime-pay-calculator.html"
  },
  {
    "id": "overtime-pay-hourly-wage-calculator-title",
    "name": "overtime-pay-hourly-wage-calculator",
    "title": "💷 Hourly Wage, Overtime & Take-Home Estimator",
    "description": "Enter your hourly rate and hours (including overtime at 1.5× or 2×, night or weekend premiums) to see weekly, monthly and annual gross pay, an approximate UK take-home after Income Tax, National In...",
    "category": "Finance & Money",
    "file": "overtime-pay-hourly-wage-calculator.html",
    "path": "cards/overtime-pay-hourly-wage-calculator.html"
  },
  {
    "id": "ovulation-fertile-window-calculator-title",
    "name": "ovulation-fertile-window-calculator",
    "title": "🌸 Ovulation & Fertile Window",
    "description": "Estimate ovulation and the fertile window from the first day of your last period and your typical cycle length. Sperm can survive up to five days, so the window starts before ovulation. Calendar me...",
    "category": "Health & Fitness",
    "file": "ovulation-fertile-window-calculator.html",
    "path": "cards/ovulation-fertile-window-calculator.html"
  },
  {
    "id": "packing-title",
    "name": "packing",
    "title": "🧳 Smart Packing List",
    "description": "Create intelligent packing lists with categories, trip types, weather considerations, and shareable checklists. Never forget an essential item!",
    "category": "Productivity & Lifestyle",
    "file": "packing.html",
    "path": "cards/packing.html"
  },
  {
    "id": "paint-calculator-title",
    "name": "paint-calculator",
    "title": "🎨 Paint Calculator",
    "description": "Calculate exactly how much paint you need for any room. No more buying 5 tins for a cupboard.",
    "category": "Home & DIY",
    "file": "paint-calculator.html",
    "path": "cards/paint-calculator.html"
  },
  {
    "id": "palette-swapper-title",
    "name": "palette-swapper",
    "title": "🎨 Advanced Palette Swapper",
    "description": "Advanced color manipulation with multiple effects, palette extraction, and real-time preview. Transform images with professional color tools!",
    "category": "Productivity & Lifestyle",
    "file": "palette-swapper.html",
    "path": "cards/palette-swapper.html"
  },
  {
    "id": "pan-size-converter-title",
    "name": "pan-size-converter",
    "title": "🥘 Pan Size Converter",
    "description": "Convert between different baking pan sizes and adjust recipes. Calculates volume differences and ingredient scaling.",
    "category": "Productivity & Lifestyle",
    "file": "pan-size-converter.html",
    "path": "cards/pan-size-converter.html"
  },
  {
    "id": "paper-size-iso-us-converter-title",
    "name": "paper-size-iso-us-converter",
    "title": "📄 Paper Size Converter",
    "description": "ISO A/B/C series, US Letter/Legal/Tabloid and pixels at print DPI. A4 is 210 × 297 mm; Letter is 8.5 × 11 in. Sizes are the ISO 216 trimmed sheet, not the printable area.",
    "category": "Productivity & Lifestyle",
    "file": "paper-size-iso-us-converter.html",
    "path": "cards/paper-size-iso-us-converter.html"
  },
  {
    "id": "parts-of-speech-trainer-title",
    "name": "parts-of-speech-trainer",
    "title": "🧠 Parts of Speech Trainer",
    "description": "Name the eight parts of speech — noun, verb, adjective, adverb, pronoun, preposition, conjunction, interjection — in 10-question rounds with hints and a reference guide.",
    "category": "Writing & Language",
    "file": "parts-of-speech-trainer.html",
    "path": "cards/parts-of-speech-trainer.html"
  },
  {
    "id": "party-title",
    "name": "party",
    "title": "Party Planner",
    "description": "Plan your party with date, location, and guest list.",
    "category": "Productivity & Lifestyle",
    "file": "party.html",
    "path": "cards/party.html"
  },
  {
    "id": "passive-aggressive-translator-title",
    "name": "passive-aggressive-translator",
    "title": "📧 Passive Aggressive Email Translator",
    "description": "Type what you actually want to say. We'll make it sound professional. Ish.",
    "category": "Productivity & Lifestyle",
    "file": "passive-aggressive-translator.html",
    "path": "cards/passive-aggressive-translator.html"
  },
  {
    "id": "passport-photo-size-guide-title",
    "name": "passport-photo-size-guide",
    "title": "🛂 Passport Photo Size Guide",
    "description": "Official print sizes and pixel dimensions for UK, US, Schengen, Canada, Australia, India and China visa photos. Face-height rules are listed — a home print can still be rejected if lighting or back...",
    "category": "Productivity & Lifestyle",
    "file": "passport-photo-size-guide.html",
    "path": "cards/passport-photo-size-guide.html"
  },
  {
    "id": "password-strength-checker-title",
    "name": "password-strength-checker",
    "title": "🔐 Password Strength Checker",
    "description": "Analyze password strength in real time. Check length, complexity, common patterns, and estimated crack time.",
    "category": "Productivity & Lifestyle",
    "file": "password-strength-checker.html",
    "path": "cards/password-strength-checker.html"
  },
  {
    "id": "password-strength-entropy-checker-title",
    "name": "password-strength-entropy-checker",
    "title": "🛡️ Password Strength & Crack-Time Estimator",
    "description": "Type a password to see its entropy in bits, estimated time to crack at online, offline and GPU-cluster speeds, and specific weaknesses — dictionary words, keyboard walks, dates, repeats and common ...",
    "category": "Algorithms & Computer Science",
    "file": "password-strength-entropy-checker.html",
    "path": "cards/password-strength-entropy-checker.html"
  },
  {
    "id": "password-title",
    "name": "password",
    "title": "Password Generator",
    "description": "Create strong, random passwords instantly. Customize length and character sets.",
    "category": "Productivity & Lifestyle",
    "file": "password.html",
    "path": "cards/password.html"
  },
  {
    "id": "pathfinding-algorithm-visualizer-title",
    "name": "pathfinding-algorithm-visualizer",
    "title": "🗺️ Pathfinding Algorithm Visualizer",
    "description": "Draw walls and watch four search algorithms hunt for the goal: DFS wanders, BFS floods evenly, Dijkstra matches BFS on a uniform grid, and A* heads straight for the target. The visited cells and th...",
    "category": "Algorithms & Computer Science",
    "file": "pathfinding-algorithm-visualizer.html",
    "path": "cards/pathfinding-algorithm-visualizer.html"
  },
  {
    "id": "pcb-trace-width-title",
    "name": "pcb-trace-width",
    "title": "⚡ PCB Trace Width Calculator",
    "description": "Estimate minimum PCB trace width for a given current, copper thickness, and temperature rise.",
    "category": "Science & Engineering",
    "file": "pcb-trace-width.html",
    "path": "cards/pcb-trace-width.html"
  },
  {
    "id": "pendulum-wave-harmonograph-title",
    "name": "pendulum-wave-harmonograph",
    "title": "🕰️ Pendulum Wave Array",
    "description": "Kinetic museum wave array. Independent pendulums with calibrated lengths execute serpentine traveling waves, choreographing standing waves and unified reconstitution.",
    "category": "Science & Engineering",
    "file": "pendulum-wave-harmonograph.html",
    "path": "cards/pendulum-wave-harmonograph.html"
  },
  {
    "id": "percentage-change-calculator-title",
    "name": "percentage-change-calculator",
    "title": "📊 Percentage Change Calculator",
    "description": "Work out the percentage increase or decrease between two numbers, plus reverse percentages and a worked price-change example.",
    "category": "Mathematics",
    "file": "percentage-change-calculator.html",
    "path": "cards/percentage-change-calculator.html"
  },
  {
    "id": "percentage-change-title",
    "name": "percentage-change",
    "title": "📈 Percentage Change Calculator",
    "description": "Calculate percentage increase or decrease between two values.",
    "category": "Productivity & Lifestyle",
    "file": "percentage-change.html",
    "path": "cards/percentage-change.html"
  },
  {
    "id": "percentages-title",
    "name": "percentages",
    "title": "📊 Advanced Percentages Explorer",
    "description": "Master percentages with advanced calculations, visualizations, and real-world applications. From basic math to financial analysis!",
    "category": "Mathematics",
    "file": "percentages.html",
    "path": "cards/percentages.html"
  },
  {
    "id": "periodic-table-explorer-title",
    "name": "periodic-table-explorer",
    "title": "⚛️ Periodic Table Explorer",
    "description": "Explore the fundamental building blocks of the universe. Search by name, symbol, or atomic number, filter by chemical series, and inspect atomic mass, electron configuration, and electronegativity.",
    "category": "Science & Engineering",
    "file": "periodic-table-explorer.html",
    "path": "cards/periodic-table-explorer.html"
  },
  {
    "id": "periodic-table-quiz-title",
    "name": "periodic-table-quiz",
    "title": "⚗️ Periodic Table Quiz",
    "description": "Learn all 118 elements — symbol to name, name to symbol, or number to name — with multiple choice, instant feedback and a searchable reference table. The whole periodic table is embedded; nothing l...",
    "category": "MrProphecy Arcade",
    "file": "periodic-table-quiz.html",
    "path": "cards/periodic-table-quiz.html"
  },
  {
    "id": "permutation-combination-title",
    "name": "permutation-combination",
    "title": "🔢 Permutations & Combinations",
    "description": "Calculate permutations (nPr) and combinations (nCr) — how many ways to arrange or select items.",
    "category": "Productivity & Lifestyle",
    "file": "permutation-combination.html",
    "path": "cards/permutation-combination.html"
  },
  {
    "id": "personal-safety-awareness-planner-title",
    "name": "personal-safety-awareness-planner",
    "title": "🛡 Personal Safety & Awareness Planner",
    "description": "Most personal-safety advice is about what to do when something is already going wrong. The useful part is earlier: noticing a situation while it is still a choice. Score a journey you are about to ...",
    "category": "Survival & Emergency Readiness",
    "file": "personal-safety-awareness-planner.html",
    "path": "cards/personal-safety-awareness-planner.html"
  },
  {
    "id": "petcare-title",
    "name": "petcare",
    "title": "Pet Care Tracker",
    "description": "Log pet care tasks like feeding, walking, or grooming.",
    "category": "Productivity & Lifestyle",
    "file": "petcare.html",
    "path": "cards/petcare.html"
  },
  {
    "id": "petty-revenge-ideas-title",
    "name": "petty-revenge-ideas",
    "title": "😈 Petty Revenge Idea Generator",
    "description": "Hilariously harmless revenge ideas for life's minor annoyances. All legal. All petty. All satisfying.",
    "category": "Productivity & Lifestyle",
    "file": "petty-revenge-ideas.html",
    "path": "cards/petty-revenge-ideas.html"
  },
  {
    "id": "phenology-gdd-calendar-lab-title",
    "name": "phenology-gdd-calendar-lab",
    "title": "🌸 Phenology & Growing Degree-Day Lab",
    "description": "Phenology is the study of seasonal timing — when leaves open, flowers bloom and swallows return. This lab models it with real growing degree-days (GDD): heat accumulated above a species-specific ba...",
    "category": "Interactive Art & Living Worlds",
    "file": "phenology-gdd-calendar-lab.html",
    "path": "cards/phenology-gdd-calendar-lab.html"
  },
  {
    "id": "photo-exposure-lab-title",
    "name": "photo-exposure-lab",
    "title": "📷 Exposure, Depth of Field & Filter Lab",
    "description": "Four things photographers work out in their heads and get wrong under pressure: what shutter speed balances a change of aperture, how long an ND filter needs, how much of the frame is actually shar...",
    "category": "Science & Engineering",
    "file": "photo-exposure-lab.html",
    "path": "cards/photo-exposure-lab.html"
  },
  {
    "id": "photon-quantum-energy-title",
    "name": "photon-quantum-energy",
    "title": "🔬 Quantum Energy Calculator",
    "description": "Calculate electromagnetic photon energy ($E = h\\nu = hc/\\lambda$), momentum ($p = h/\\lambda$), and matter wave de Broglie wavelengths across the entire electromagnetic radiation spectrum.",
    "category": "Science & Engineering",
    "file": "photon-quantum-energy.html",
    "path": "cards/photon-quantum-energy.html"
  },
  {
    "id": "physics-unit-converter-matrix-title",
    "name": "physics-unit-converter-matrix",
    "title": "🔄 Universal Unit Matrix",
    "description": "High-precision bidirectional converter across engineering, data storage, scientific physics, and everyday measurements.",
    "category": "Science & Engineering",
    "file": "physics-unit-converter-matrix.html",
    "path": "cards/physics-unit-converter-matrix.html"
  },
  {
    "id": "physics-title",
    "name": "physics",
    "title": "🔬 Physics Toolkit",
    "description": "Calculate common physics formulas: motion, forces, energy, and more. Select a formula to begin.",
    "category": "Science & Engineering",
    "file": "physics.html",
    "path": "cards/physics.html"
  },
  {
    "id": "picture-hanging-guide-title",
    "name": "picture-hanging-guide",
    "title": "🖼️ Picture Hanging Calculator",
    "description": "Calculate the perfect height and hook position so your pictures hang straight and look professional.",
    "category": "Home & DIY",
    "file": "picture-hanging-guide.html",
    "path": "cards/picture-hanging-guide.html"
  },
  {
    "id": "pigment-cabinet-of-colour-title",
    "name": "pigment-cabinet-of-colour",
    "title": "🎨 The Pigment Cabinet",
    "description": "Colour as a dated substance. Each pot is a first-use, a chemistry, and a verdict: still on the palette, replaced, or locked in the poison cupboard. Swatches are screen approximations — never a spec...",
    "category": "Museum & Collection",
    "file": "pigment-cabinet-of-colour.html",
    "path": "cards/pigment-cabinet-of-colour.html"
  },
  {
    "id": "pipe-flow-simulator-title",
    "name": "pipe-flow-simulator",
    "title": "💧 The Pipe Lab",
    "description": "Watch water flow through pipes in real time. See Bernoulli's principle in action — where the pipe narrows, water speeds up and pressure drops. Particles show laminar vs turbulent flow. Adjust diame...",
    "category": "Museum & Collection",
    "file": "pipe-flow-simulator.html",
    "path": "cards/pipe-flow-simulator.html"
  },
  {
    "id": "pixel-collaborative-infinite-mural-title",
    "name": "pixel-collaborative-infinite-mural",
    "title": "🎨 PixelVerse Canvas",
    "description": "An evolving communal pixel art tapestry. Paint with friends over time, record generational brushstrokes, watch the creation time-lapse from inception, and export high-res artwork without paywalls.",
    "category": "Interactive Art & Living Worlds",
    "file": "pixel-collaborative-infinite-mural.html",
    "path": "cards/pixel-collaborative-infinite-mural.html"
  },
  {
    "id": "pizza-dough-calculator-title",
    "name": "pizza-dough-calculator",
    "title": "🍕 Pizza Dough Ferment Master",
    "description": "Artisan pizza dough formula engine supporting Neapolitan (AVPN), New York Style, Detroit Pan, and Roman Al Taglio. Computes baker's percentages, cold fermentation schedules, and yeast scaling.",
    "category": "Culinary & Food Science",
    "file": "pizza-dough-calculator.html",
    "path": "cards/pizza-dough-calculator.html"
  },
  {
    "id": "plagiarism-check-title",
    "name": "plagiarism-check",
    "title": "🔍 Plagiarism Checker",
    "description": "Check text for originality and similarity with common phrases. Local processing only — no data sent online.",
    "category": "Writing & Language",
    "file": "plagiarism-check.html",
    "path": "cards/plagiarism-check.html"
  },
  {
    "id": "plain-language-decoder-title",
    "name": "plain-language-decoder",
    "title": "📖 Plain Language Decoder",
    "description": "Paste a letter, contract clause, medical note or official notice and get it back in ordinary English, with the obligations and deadlines pulled out separately. Runs entirely on your device — nothin...",
    "category": "Wellbeing & Community",
    "file": "plain-language-decoder.html",
    "path": "cards/plain-language-decoder.html"
  },
  {
    "id": "planet-ring-designer-3d-title",
    "name": "planet-ring-designer-3d",
    "title": "🪐 Planet & Ring Designer 3D",
    "description": "Build your own ringed world: gas giants with racing storms, lava planets with glowing cracks, tilted Keplerian rings where inner particles genuinely orbit faster, and up to three moons. Every world...",
    "category": "Astronomy & Space",
    "file": "planet-ring-designer-3d.html",
    "path": "cards/planet-ring-designer-3d.html"
  },
  {
    "id": "planet-surface-3d-explorer-title",
    "name": "planet-surface-3d-explorer",
    "title": "🌍 Planet Surface 3D Explorer",
    "description": "Land on every world like an astronaut with a telescope: a real 3D sphere you can spin, tilt and zoom, textured per planet from real features — Mercury's craters, Venus's hidden iron-peaked clouds, ...",
    "category": "Astronomy & Space",
    "file": "planet-surface-3d-explorer.html",
    "path": "cards/planet-surface-3d-explorer.html"
  },
  {
    "id": "plant-encyclopedia-title",
    "name": "plant-encyclopedia",
    "title": "🌿 Plant Encyclopedia (Live)",
    "description": "Comprehensive plant database with real-time data from multiple sources. Search for any plant to get detailed information.",
    "category": "Science & Engineering",
    "file": "plant-encyclopedia.html",
    "path": "cards/plant-encyclopedia.html"
  },
  {
    "id": "plastering-calculator-title",
    "name": "plastering-calculator",
    "title": "🪣 Plastering Calculator",
    "description": "Calculate how much plaster, render, or screed you need for walls, ceilings, or floors. Includes bags, coverage, and estimated cost.",
    "category": "Home & DIY",
    "file": "plastering-calculator.html",
    "path": "cards/plastering-calculator.html"
  },
  {
    "id": "plumbing-pipe-sizing-title",
    "name": "plumbing-pipe-sizing",
    "title": "🔧 Pipe Sizing Guide",
    "description": "Look up the right pipe diameter for any domestic plumbing job. Covers hot/cold water, central heating, and waste.",
    "category": "Home & DIY",
    "file": "plumbing-pipe-sizing.html",
    "path": "cards/plumbing-pipe-sizing.html"
  },
  {
    "id": "poison-chemical-exposure-response-title",
    "name": "poison-chemical-exposure-response",
    "title": "☣️ Poison & Chemical Exposure Response",
    "description": "The first ninety seconds after a poisoning are mostly about not making it worse, and most of the folk advice is actively dangerous. Find the substance, pick how it got in, and get the specific firs...",
    "category": "Survival & Emergency Readiness",
    "file": "poison-chemical-exposure-response.html",
    "path": "cards/poison-chemical-exposure-response.html"
  },
  {
    "id": "polyhedral-dice-3d-roller-title",
    "name": "polyhedral-dice-3d-roller",
    "title": "🎲 Polyhedral Dice 3D Roller",
    "description": "Real tumbling 3D dice — D4 through D20 — rendered as true platonic solids. The die physically rotates so your rolled face lands front-and-centre. Includes roll history, fairness stats and a 100-rol...",
    "category": "Virtual Worlds & Gaming",
    "file": "polyhedral-dice-3d-roller.html",
    "path": "cards/polyhedral-dice-3d-roller.html"
  },
  {
    "id": "pomodoro-flow-title",
    "name": "pomodoro-flow",
    "title": "⏱️ Pomodoro Flow Timer",
    "description": "Level up your daily productivity with science-backed 25-minute focus intervals, audio finish chimes, streak tracking, and gamified XP rewards for completed sprints.",
    "category": "Productivity & Lifestyle",
    "file": "pomodoro-flow.html",
    "path": "cards/pomodoro-flow.html"
  },
  {
    "id": "pool-spa-volume-calculator-title",
    "name": "pool-spa-volume-calculator",
    "title": "🏊 Pool & Spa Volume",
    "description": "Litres and gallons from length, width and average depth. Rectangular, circular and oval. Chemical dosing is per 1,000 litres — this is volume only, not a treatment plan.",
    "category": "Home & DIY",
    "file": "pool-spa-volume-calculator.html",
    "path": "cards/pool-spa-volume-calculator.html"
  },
  {
    "id": "poultice-compress-remedy-lab-title",
    "name": "poultice-compress-remedy-lab",
    "title": "🩹 Herbal Poultice & Compress",
    "description": "Topical acute botanical applications (fomentations & cataplasms). Formulates venom drawing pastes, bone-healing comfrey packs, and castor oil compresses.",
    "category": "Natural Remedies & Herbs",
    "file": "poultice-compress-remedy-lab.html",
    "path": "cards/poultice-compress-remedy-lab.html"
  },
  {
    "id": "power-calculator-title",
    "name": "power-calculator",
    "title": "⚡ Power Calculator",
    "description": "Calculate electrical power values with multiple calculation modes. ⚠️ Educational purposes only — consult licensed electrician for actual installations.",
    "category": "Science & Engineering",
    "file": "power-calculator.html",
    "path": "cards/power-calculator.html"
  },
  {
    "id": "powerlifting-dots-wilks-score-title",
    "name": "powerlifting-dots-wilks-score",
    "title": "🏋️ Powerlifting DOTS & Wilks Score",
    "description": "Compare lifters across weight classes. Enter a bodyweight and total (or the three lifts) and get both the modern DOTS score and the classic Wilks score, so a 60 kg lifter and a 120 kg lifter can be...",
    "category": "Sports",
    "file": "powerlifting-dots-wilks-score.html",
    "path": "cards/powerlifting-dots-wilks-score.html"
  },
  {
    "id": "practice-tracker-title",
    "name": "practice-tracker",
    "title": "🎯 Practice Tracker",
    "description": "Track and analyze your practice sessions with detailed metrics and progress visualization. Set goals, track habits, and measure improvement.",
    "category": "Productivity & Lifestyle",
    "file": "practice-tracker.html",
    "path": "cards/practice-tracker.html"
  },
  {
    "id": "pregnancy-due-date-calculator-title",
    "name": "pregnancy-due-date-calculator",
    "title": "🤰 Pregnancy Due Date Calculator",
    "description": "Estimate a due date with Naegele’s rule from the last menstrual period, or work backwards from a known due date. Shows gestational week, trimester and days remaining. This is an educational estimat...",
    "category": "Health & Fitness",
    "file": "pregnancy-due-date-calculator.html",
    "path": "cards/pregnancy-due-date-calculator.html"
  },
  {
    "id": "pregnancy-due-date-week-calculator-title",
    "name": "pregnancy-due-date-week-calculator",
    "title": "🤰 Pregnancy Due Date & Week-by-Week Calculator",
    "description": "Estimate your due date from the first day of your last period, conception date, IVF transfer or a scan-dated due date. See how many weeks and days pregnant you are today, the current trimester, key...",
    "category": "Health & Fitness",
    "file": "pregnancy-due-date-week-calculator.html",
    "path": "cards/pregnancy-due-date-week-calculator.html"
  },
  {
    "id": "pregnancy-weight-gain-guide-title",
    "name": "pregnancy-weight-gain-guide",
    "title": "🤰 Pregnancy Weight Gain Guide",
    "description": "IOM/NAM ranges by pre-pregnancy BMI for a singleton: underweight 12.5–18 kg, healthy 11.5–16 kg, overweight 7–11.5 kg, obese 5–9 kg. A sketch for conversations with a midwife — not a target you mus...",
    "category": "Health & Fitness",
    "file": "pregnancy-weight-gain-guide.html",
    "path": "cards/pregnancy-weight-gain-guide.html"
  },
  {
    "id": "premier-league-title",
    "name": "premier-league",
    "title": "⚽ Premier League Live",
    "description": "Live Premier League data scraped from current online sources. Teams update automatically.",
    "category": "Sports",
    "file": "premier-league.html",
    "path": "cards/premier-league.html"
  },
  {
    "id": "price-in-work-hours-title",
    "name": "price-in-work-hours",
    "title": "⏱️ Price Tag in Hours of Your Life",
    "description": "Money is frozen time. Convert any price into how many hours (and minutes) of your actual working life it costs — after tax, before snacks. That latte is cheaper once you've seen it in minutes.",
    "category": "Productivity & Lifestyle",
    "file": "price-in-work-hours.html",
    "path": "cards/price-in-work-hours.html"
  },
  {
    "id": "prime-factorisation-trainer-title",
    "name": "prime-factorisation-trainer",
    "title": "🧮 Prime Factorisation Trainer",
    "description": "Break any number into its prime factors with a full working ladder, learn the divisibility rules, then practise finding the next prime factor yourself. Primes are the building blocks of every whole...",
    "category": "Mathematics",
    "file": "prime-factorisation-trainer.html",
    "path": "cards/prime-factorisation-trainer.html"
  },
  {
    "id": "prime-number-checker-title",
    "name": "prime-number-checker",
    "title": "🔢 Prime Number Checker",
    "description": "Test whether n is prime, list its prime factors, and jump to the next prime. Trial division up to √n — fine for integers up to about 10¹² in this browser. 1 is not prime.",
    "category": "Mathematics",
    "file": "prime-number-checker.html",
    "path": "cards/prime-number-checker.html"
  },
  {
    "id": "print-dpi-photo-size-calculator-title",
    "name": "print-dpi-photo-size-calculator",
    "title": "🖨️ Print Size & DPI Calculator",
    "description": "Convert pixel dimensions to print size at a chosen DPI, or the other way around. 300 DPI is typical photo-lab quality; 150 DPI is fine for posters viewed from a few feet.",
    "category": "Productivity & Lifestyle",
    "file": "print-dpi-photo-size-calculator.html",
    "path": "cards/print-dpi-photo-size-calculator.html"
  },
  {
    "id": "prism-optics-ray-refraction-title",
    "name": "prism-optics-ray-refraction",
    "title": "🌈 Prism Optics & Snell's Law",
    "description": "Interactive optical bench simulating chromatic dispersion, Snell's law refraction, and total internal reflection (TIR) through a triangular prism.",
    "category": "Science & Engineering",
    "file": "prism-optics-ray-refraction.html",
    "path": "cards/prism-optics-ray-refraction.html"
  },
  {
    "id": "pro-rata-salary-calculator-title",
    "name": "pro-rata-salary-calculator",
    "title": "💷 Pro Rata Salary Calculator",
    "description": "Scale a full-time equivalent salary to part-time hours, or the other way. Uses working hours only — not tax, NI, or pension. UK job ads often quote FTE then “pro rata”.",
    "category": "Finance & Money",
    "file": "pro-rata-salary-calculator.html",
    "path": "cards/pro-rata-salary-calculator.html"
  },
  {
    "id": "probability-paradox-lab-title",
    "name": "probability-paradox-lab",
    "title": "🎲 Probability Paradox Lab",
    "description": "Your gut feeling about chance is usually wrong — prove it to yourself. Simulate the Monty Hall problem, the birthday paradox and coin-flip streaks with thousands of instant trials.",
    "category": "Mathematics",
    "file": "probability-paradox-lab.html",
    "path": "cards/probability-paradox-lab.html"
  },
  {
    "id": "probability-title",
    "name": "probability",
    "title": "🎲 Probability Calculator",
    "description": "Calculate probabilities for dice, cards, distributions, and real-world scenarios.",
    "category": "Mathematics",
    "file": "probability.html",
    "path": "cards/probability.html"
  },
  {
    "id": "procrastination-justifier-title",
    "name": "procrastination-justifier",
    "title": "🕐 Procrastination Justifier",
    "description": "Scientifically* valid reasons why you should absolutely do that thing tomorrow instead. *Not scientifically valid.",
    "category": "Productivity & Lifestyle",
    "file": "procrastination-justifier.html",
    "path": "cards/procrastination-justifier.html"
  },
  {
    "id": "productivityscore-title",
    "name": "productivityscore",
    "title": "🚀 Productivity Score",
    "description": "Calculate and analyze your daily productivity with detailed insights and actionable recommendations. Track progress and optimize your workflow.",
    "category": "Productivity & Lifestyle",
    "file": "productivityscore.html",
    "path": "cards/productivityscore.html"
  },
  {
    "id": "project-profitability-estimator-title",
    "name": "project-profitability-estimator",
    "title": "📊 Project Profitability Estimator",
    "description": "Quote client projects from real labour, expenses and contingency while protecting a target profit margin. All calculations stay in your browser.",
    "category": "Finance & Money",
    "file": "project-profitability-estimator.html",
    "path": "cards/project-profitability-estimator.html"
  },
  {
    "id": "projectdeadline-title",
    "name": "projectdeadline",
    "title": "📅 Project Deadline Calculator",
    "description": "Calculate project timelines with buffer days, weekend exclusions, and milestone planning. Plan realistically and track progress.",
    "category": "Productivity & Lifestyle",
    "file": "projectdeadline.html",
    "path": "cards/projectdeadline.html"
  },
  {
    "id": "projectile-motion-simulator-title",
    "name": "projectile-motion-simulator",
    "title": "🎯 Projectile Motion Simulator",
    "description": "Simulate parabolic ballistic trajectories in real time across different planetary gravitational fields. Computes flight time, apex altitude, total ground range, and impact velocity.",
    "category": "Science & Engineering",
    "file": "projectile-motion-simulator.html",
    "path": "cards/projectile-motion-simulator.html"
  },
  {
    "id": "projector-throw-distance-calculator-title",
    "name": "projector-throw-distance-calculator",
    "title": "📽️ Projector Throw Distance",
    "description": "Throw ratio = distance to screen ÷ image width. A 1.5:1 lens 3 m from the wall makes a 2 m wide picture. 16:9 assumed unless you change it. Check the projector’s own min/max zoom range.",
    "category": "Home & DIY",
    "file": "projector-throw-distance-calculator.html",
    "path": "cards/projector-throw-distance-calculator.html"
  },
  {
    "id": "prompt-architect-title",
    "name": "prompt-architect",
    "title": "⚡ AI Prompt Studio",
    "description": "Turn vague thoughts into high-performance AI prompts used by senior prompt engineers. Constructs rigorous prompts with Chain-of-Thought reasoning, XML delimiters, output schemas, and anti-hallucina...",
    "category": "Productivity & Lifestyle",
    "file": "prompt-architect.html",
    "path": "cards/prompt-architect.html"
  },
  {
    "id": "proofreading-title",
    "name": "proofreading",
    "title": "✍️ Proofreading & Style Checker",
    "description": "Advanced text analysis for grammar, style, readability, and clarity. Get detailed suggestions with explanations.",
    "category": "Writing & Language",
    "file": "proofreading.html",
    "path": "cards/proofreading.html"
  },
  {
    "id": "protein-daily-intake-calculator-title",
    "name": "protein-daily-intake-calculator",
    "title": "🥩 Daily Protein Intake",
    "description": "Estimate a daily protein target from body weight and how hard you train. Sedentary adults often sit near 0.8 g/kg; strength athletes commonly use 1.6–2.2 g/kg. Not a prescription — kidney disease n...",
    "category": "Health & Fitness",
    "file": "protein-daily-intake-calculator.html",
    "path": "cards/protein-daily-intake-calculator.html"
  },
  {
    "id": "psychrometric-dewpoint-analyzer-title",
    "name": "psychrometric-dewpoint-analyzer",
    "title": "☁️ Psychrometric & Dew Point",
    "description": "Analyze atmospheric water vapor psychrometrics using Magnus-Tetens formulas. Calculate exact Dew Point ($T_{dp}$), saturation vapor pressure ($e_s$), moisture humidity ratio ($W$), and surface cond...",
    "category": "Science & Engineering",
    "file": "psychrometric-dewpoint-analyzer.html",
    "path": "cards/psychrometric-dewpoint-analyzer.html"
  },
  {
    "id": "public-speaking-title",
    "name": "public-speaking",
    "title": "🎤 Public Speaking Coach",
    "description": "Improve your speeches with AI-powered analysis, practice tools, and personalized feedback. Practice timing, structure, delivery, and confidence.",
    "category": "Writing & Language",
    "file": "public-speaking.html",
    "path": "cards/public-speaking.html"
  },
  {
    "id": "punctuation-guide-title",
    "name": "punctuation-guide",
    "title": "📝 Punctuation Mastery Guide",
    "description": "Master the art of punctuation with this comprehensive guide. Learn rules, see examples, and test your knowledge. Perfect for writers, students, and professionals!",
    "category": "Writing & Language",
    "file": "punctuation-guide.html",
    "path": "cards/punctuation-guide.html"
  },
  {
    "id": "puppy-adult-weight-predictor-title",
    "name": "puppy-adult-weight-predictor",
    "title": "🐾 Puppy Adult Weight Forecaster",
    "description": "Canine Gompertz growth velocity forecaster. Predicts final adult weight based on current puppy weight, age in weeks, and breed skeletal frame category.",
    "category": "Dogs & Canine Care",
    "file": "puppy-adult-weight-predictor.html",
    "path": "cards/puppy-adult-weight-predictor.html"
  },
  {
    "id": "px-rem-em-unit-converter-title",
    "name": "px-rem-em-unit-converter",
    "title": "↔️ px ⇄ rem ⇄ em Converter",
    "description": "Convert CSS lengths between pixels, rem and em for a chosen root and parent font size. Defaults to the browser 16 px root. Copy-ready declarations, no build step.",
    "category": "Algorithms & Computer Science",
    "file": "px-rem-em-unit-converter.html",
    "path": "cards/px-rem-em-unit-converter.html"
  },
  {
    "id": "pythagoras-calculator-title",
    "name": "pythagoras-calculator",
    "title": "📐 Pythagoras Calculator",
    "description": "Find the missing side of a right-angled triangle with the Pythagorean theorem — plus the area, perimeter and both acute angles.",
    "category": "Mathematics",
    "file": "pythagoras-calculator.html",
    "path": "cards/pythagoras-calculator.html"
  },
  {
    "id": "pythagoras-triangle-solver-title",
    "name": "pythagoras-triangle-solver",
    "title": "△ Pythagoras Triangle Solver",
    "description": "Right-angled triangle: a² + b² = c². Leave one side blank (or 0) and it is solved. Optional acute angle (degrees) uses SOH-CAH-TOA with the opposite/adjacent/hypotenuse you fill.",
    "category": "Mathematics",
    "file": "pythagoras-triangle-solver.html",
    "path": "cards/pythagoras-triangle-solver.html"
  },
  {
    "id": "qr-code-generator-title",
    "name": "qr-code-generator",
    "title": "📱 QR Code Generator",
    "description": "Generate QR codes instantly — all processing happens in your browser. No data leaves your device. Supports URLs, text, WiFi, email, and more.",
    "category": "Productivity & Lifestyle",
    "file": "qr-code-generator.html",
    "path": "cards/qr-code-generator.html"
  },
  {
    "id": "qr-code-reader-scanner-title",
    "name": "qr-code-reader-scanner",
    "title": "📷 Instant QR & Image Reader",
    "description": "Decode QR codes instantly from uploaded screenshots, images, or your live camera feed. 100% private in-browser decoding — photos never leave your device.",
    "category": "Productivity & Lifestyle",
    "file": "qr-code-reader-scanner.html",
    "path": "cards/qr-code-reader-scanner.html"
  },
  {
    "id": "qr-title",
    "name": "qr",
    "title": "📊 Barcode Check Digit Validator",
    "description": "Validate or generate the check digit for EAN-13, UPC-A, EAN-8, ISBN-13, ISBN-10, GTIN-14 and ITF-14 barcodes. Shows the arithmetic so you can see exactly why a code passes or fails.",
    "category": "Productivity & Lifestyle",
    "file": "qr.html",
    "path": "cards/qr.html"
  },
  {
    "id": "qrtool-title",
    "name": "qrtool",
    "title": "🔳 Advanced QR Generator",
    "description": "Create professional QR codes with custom styling, analytics tracking, and bulk generation. Supports URLs, WiFi, contact cards, and dynamic content.",
    "category": "Productivity & Lifestyle",
    "file": "qrtool.html",
    "path": "cards/qrtool.html"
  },
  {
    "id": "qtc-heart-interval-calculator-title",
    "name": "qtc-heart-interval-calculator",
    "title": "❤️ QTc Interval (Bazett)",
    "description": "QTc (Bazett) = QT ÷ √(RR), with RR = 60 / heart-rate. Also shows Fridericia (QT ÷ RR⅓). Educational arithmetic from numbers you type — not an ECG, not a diagnosis. Chest pain or syncope needs emerg...",
    "category": "Health & Fitness",
    "file": "qtc-heart-interval-calculator.html",
    "path": "cards/qtc-heart-interval-calculator.html"
  },
  {
    "id": "quadratic-equation-solver-title",
    "name": "quadratic-equation-solver",
    "title": "𝑥² Quadratic Equation Solver",
    "description": "Roots of ax² + bx + c = 0 via the discriminant Δ = b² − 4ac. Complex roots are shown as a ± bi. Coefficients can be any real numbers, with a ≠ 0.",
    "category": "Mathematics",
    "file": "quadratic-equation-solver.html",
    "path": "cards/quadratic-equation-solver.html"
  },
  {
    "id": "quadratic-solver-title",
    "name": "quadratic-solver",
    "title": "🧮 Quadratic Equation Solver",
    "description": "Solve ax² + bx + c = 0 with the quadratic formula — real or complex roots, with every step shown.",
    "category": "Mathematics",
    "file": "quadratic-solver.html",
    "path": "cards/quadratic-solver.html"
  },
  {
    "id": "quantum-wave-packet-tunneling-title",
    "name": "quantum-wave-packet-tunneling",
    "title": "⚛️ Quantum Wave Tunneling",
    "description": "Quantum mechanical wavepacket simulator solving the time-dependent Schrödinger equation across an impenetrable classical potential barrier.",
    "category": "Science & Engineering",
    "file": "quantum-wave-packet-tunneling.html",
    "path": "cards/quantum-wave-packet-tunneling.html"
  },
  {
    "id": "query-string-parser-title",
    "name": "query-string-parser",
    "title": "🔗 Query String Parser",
    "description": "Split a URL or a raw ?a=1&b=2 into keys. Duplicate keys become arrays. Build the other way from JSON. Uses the platform URLSearchParams — stays on this device.",
    "category": "Algorithms & Computer Science",
    "file": "query-string-parser.html",
    "path": "cards/query-string-parser.html"
  },
  {
    "id": "quilt-tapestry-geometric-mosaic-title",
    "name": "quilt-tapestry-geometric-mosaic",
    "title": "🧵 QuiltWeaver Tapestry",
    "description": "Weave an evolving mathematical patchwork tapestry with friends. Design geometric quilt blocks using wallpaper group symmetries, Truchet curves, and Islamic rosettes, then stitch them into a shared ...",
    "category": "Interactive Art & Living Worlds",
    "file": "quilt-tapestry-geometric-mosaic.html",
    "path": "cards/quilt-tapestry-geometric-mosaic.html"
  },
  {
    "id": "quiz-maker-title",
    "name": "quiz-maker",
    "title": "🧠 Quick Quiz Maker",
    "description": "Create a multiple-choice quiz, then test yourself. Questions save to your browser.",
    "category": "Productivity & Lifestyle",
    "file": "quiz-maker.html",
    "path": "cards/quiz-maker.html"
  },
  {
    "id": "quiz-title",
    "name": "quiz",
    "title": "🎯 Smart Quiz Generator",
    "description": "Create custom quizzes, track progress, and test your knowledge. Perfect for studying, training, or self-assessment. Add multiple choice, true/false, or open-ended questions!",
    "category": "Productivity & Lifestyle",
    "file": "quiz.html",
    "path": "cards/quiz.html"
  },
  {
    "id": "race-pace-predictor-title",
    "name": "race-pace-predictor",
    "title": "🏃 Race Pace Predictor & Training Paces",
    "description": "Enter one recent race you actually ran, honestly, and this predicts the rest, gives you the pace to hold per kilometre or mile, and turns it into the five training paces you actually need. Predicti...",
    "category": "Sports",
    "file": "race-pace-predictor.html",
    "path": "cards/race-pace-predictor.html"
  },
  {
    "id": "radians-degrees-converter-title",
    "name": "radians-degrees-converter",
    "title": "∠ Radians ⇄ Degrees Converter",
    "description": "π rad = 180°. Also shows revolutions and a reduced π-fraction when it is close to a simple multiple of π.",
    "category": "Mathematics",
    "file": "radians-degrees-converter.html",
    "path": "cards/radians-degrees-converter.html"
  },
  {
    "id": "radioactive-decay-calculator-title",
    "name": "radioactive-decay-calculator",
    "title": "☢️ Radioactive Decay Lab",
    "description": "Model exponential nuclear decay, remaining isotope fractions, and radiometric carbon dating via the fundamental decay law $N(t) = N_0 (1/2)^{t / t_{1/2}}$.",
    "category": "Science & Engineering",
    "file": "radioactive-decay-calculator.html",
    "path": "cards/radioactive-decay-calculator.html"
  },
  {
    "id": "rain-shadow-orographic-lift-lab-title",
    "name": "rain-shadow-orographic-lift-lab",
    "title": "⛰️ Rain Shadow & Orographic Lift Lab",
    "description": "Push a parcel of air over a mountain and watch geography make weather. This lifts your air dry-adiabatically to the cloud base, integrates a proper saturated adiabat over the summit — the lapse rat...",
    "category": "Interactive Art & Living Worlds",
    "file": "rain-shadow-orographic-lift-lab.html",
    "path": "cards/rain-shadow-orographic-lift-lab.html"
  },
  {
    "id": "rainwater-harvest-calculator-title",
    "name": "rainwater-harvest-calculator",
    "title": "🌧️ Rainwater Harvest",
    "description": "1 mm of rain on 1 m² is 1 litre. Multiply by a runoff coefficient (tiles ~0.85, felt ~0.8). UK roofs often yield more than a water-butt can hold — size the tank, not just the dream.",
    "category": "Home & DIY",
    "file": "rainwater-harvest-calculator.html",
    "path": "cards/rainwater-harvest-calculator.html"
  },
  {
    "id": "rainwater-harvest-tank-simulator-title",
    "name": "rainwater-harvest-tank-simulator",
    "title": "🪣 Rainwater Harvesting & Tank Simulator",
    "description": "Everyone sizes a water butt by guessing. This runs a day-by-day simulation of a whole year — rain falling on your roof, water drawn off, the tank filling, overflowing and running dry — then sweeps ...",
    "category": "Interactive Art & Living Worlds",
    "file": "rainwater-harvest-tank-simulator.html",
    "path": "cards/rainwater-harvest-tank-simulator.html"
  },
  {
    "id": "random-number-dice-coin-generator-title",
    "name": "random-number-dice-coin-generator",
    "title": "🎲 Random Number, Dice & Coin",
    "description": "Roll dice, flip a coin or draw integers in a range. Uses the Web Crypto API when the browser has it, so results are suitable for raffles and tabletop — not for cryptographic keys.",
    "category": "Productivity & Lifestyle",
    "file": "random-number-dice-coin-generator.html",
    "path": "cards/random-number-dice-coin-generator.html"
  },
  {
    "id": "random-number-dice-picker-title",
    "name": "random-number-dice-picker",
    "title": "🎲 Random Number, Dice & Name Picker",
    "description": "Cryptographically random numbers in any range (with or without repeats), dice rolls in D&D notation like 3d6+2, coin flips, and a fair picker that draws a winner or shuffles a list of names. Nothin...",
    "category": "Productivity & Lifestyle",
    "file": "random-number-dice-picker.html",
    "path": "cards/random-number-dice-picker.html"
  },
  {
    "id": "random-number-generator-title",
    "name": "random-number-generator",
    "title": "🎲 Random Number Generator",
    "description": "Generate random numbers within any range. Supports integers, decimals, multiple values, and custom distributions.",
    "category": "Productivity & Lifestyle",
    "file": "random-number-generator.html",
    "path": "cards/random-number-generator.html"
  },
  {
    "id": "ratio-proportion-calculator-title",
    "name": "ratio-proportion-calculator",
    "title": "➗ Ratio & Proportion",
    "description": "Solve a/b = c/d for the blank, simplify a ratio, and scale a recipe-style mix. Leave exactly one of A, B, C, D empty. Cross-multiply: A × D = B × C.",
    "category": "Mathematics",
    "file": "ratio-proportion-calculator.html",
    "path": "cards/ratio-proportion-calculator.html"
  },
  {
    "id": "raycast-pocket-dungeon-title",
    "name": "raycast-pocket-dungeon",
    "title": "🗝️ Raycast Pocket Dungeon",
    "description": "A Wolfenstein-style 3D dungeon in pure maths — no game engine. Procedurally generated maze, glowing orb collectibles, a portal exit, minimap and touch controls. Click the view, then use WASD or arr...",
    "category": "Virtual Worlds & Gaming",
    "file": "raycast-pocket-dungeon.html",
    "path": "cards/raycast-pocket-dungeon.html"
  },
  {
    "id": "rc-time-constant-calculator-title",
    "name": "rc-time-constant-calculator",
    "title": "⏲️ RC Time Constant",
    "description": "τ = R × C. A capacitor charges to ~63% in one τ and ~99% in 5τ. Cut-off of a first-order RC low-pass is fc = 1 / (2πRC). R in ohms, C in farads (enter µF).",
    "category": "Science & Engineering",
    "file": "rc-time-constant-calculator.html",
    "path": "cards/rc-time-constant-calculator.html"
  },
  {
    "id": "reaction-diffusion-turing-patterns-title",
    "name": "reaction-diffusion-turing-patterns",
    "title": "🐆 Turing Reaction Diffusion",
    "description": "Alan Turing's 1952 morphogenesis simulator. Nonlinear chemical reaction-diffusion equations generating biological spots, stripes, and coral textures.",
    "category": "Science & Engineering",
    "file": "reaction-diffusion-turing-patterns.html",
    "path": "cards/reaction-diffusion-turing-patterns.html"
  },
  {
    "id": "readability-score-title",
    "name": "readability-score",
    "title": "📊 Readability Analyzer",
    "description": "Analyze text readability with multiple scoring systems. Get actionable insights to improve your writing for any audience. Supports 8+ readability formulas with visual feedback!",
    "category": "Writing & Language",
    "file": "readability-score.html",
    "path": "cards/readability-score.html"
  },
  {
    "id": "reading-timer-title",
    "name": "reading-timer",
    "title": "⏱️ Pace Reading Timer",
    "description": "Time yourself reading a passage to measure your words-per-minute rate.",
    "category": "Productivity & Lifestyle",
    "file": "reading-timer.html",
    "path": "cards/reading-timer.html"
  },
  {
    "id": "readingtime-title",
    "name": "readingtime",
    "title": "📚 Reading Time Calculator",
    "description": "Calculate precise reading time estimates with multiple input methods, audience presets, and detailed breakdowns. Perfect for writers, editors, and content creators!",
    "category": "Writing & Language",
    "file": "readingtime.html",
    "path": "cards/readingtime.html"
  },
  {
    "id": "reality-dimensions-title",
    "name": "reality-dimensions",
    "title": "📐 Dimensions of Reality",
    "description": "We live in 3 spatial dimensions — but why 3? Explore what life would be like in 1D, 2D, 4D, and beyond. Each dimension changes the laws of physics.",
    "category": "Science & Engineering",
    "file": "reality-dimensions.html",
    "path": "cards/reality-dimensions.html"
  },
  {
    "id": "reality-emergence-title",
    "name": "reality-emergence",
    "title": "🌀 Emergence — Simple Rules, Infinite Complexity",
    "description": "Watch Conway's Game of Life: 4 simple rules create self-replicating patterns, computation, and open-ended complexity from nothing.",
    "category": "Science & Engineering",
    "file": "reality-emergence.html",
    "path": "cards/reality-emergence.html"
  },
  {
    "id": "reality-entropy-arrow-of-time-title",
    "name": "reality-entropy-arrow-of-time",
    "title": "🔄 Entropy & The Arrow of Time",
    "description": "Why does time only flow forward? Watch entropy increase in real-time as ordered systems dissolve into disorder — the fundamental law that gives time its direction.",
    "category": "Science & Engineering",
    "file": "reality-entropy-arrow-of-time.html",
    "path": "cards/reality-entropy-arrow-of-time.html"
  },
  {
    "id": "reality-fundamental-constants-title",
    "name": "reality-fundamental-constants",
    "title": "🔢 The Constants of Reality",
    "description": "The universe is governed by a handful of numbers. Change any one of them slightly — and atoms, stars, chemistry, and life cannot exist. Why these numbers?",
    "category": "Science & Engineering",
    "file": "reality-fundamental-constants.html",
    "path": "cards/reality-fundamental-constants.html"
  },
  {
    "id": "reality-observer-effect-title",
    "name": "reality-observer-effect",
    "title": "👁️ The Observer Effect",
    "description": "Does observation change reality? Explore the measurement problem, Schrödinger's cat, and the role of the observer in quantum mechanics.",
    "category": "Science & Engineering",
    "file": "reality-observer-effect.html",
    "path": "cards/reality-observer-effect.html"
  },
  {
    "id": "reality-quantum-world-title",
    "name": "reality-quantum-world",
    "title": "⚛️ The Quantum World",
    "description": "Explore wave-particle duality, superposition, and the measurement problem. Fire particles through slits and watch reality behave impossibly.",
    "category": "Science & Engineering",
    "file": "reality-quantum-world.html",
    "path": "cards/reality-quantum-world.html"
  },
  {
    "id": "reality-scale-of-reality-title",
    "name": "reality-scale-of-reality",
    "title": "🌌 Scale of Reality",
    "description": "Zoom from the Planck length (10⁻³⁵m) to the observable universe (10²⁷m). Drag the slider to see where you exist in the full scale of reality.",
    "category": "Science & Engineering",
    "file": "reality-scale-of-reality.html",
    "path": "cards/reality-scale-of-reality.html"
  },
  {
    "id": "reality-spacetime-curvature-title",
    "name": "reality-spacetime-curvature",
    "title": "🕳️ Spacetime Curvature",
    "description": "See how mass warps the fabric of spacetime. Drag the mass slider to watch gravity bend space, slow time, and curve the paths of light.",
    "category": "Science & Engineering",
    "file": "reality-spacetime-curvature.html",
    "path": "cards/reality-spacetime-curvature.html"
  },
  {
    "id": "reality-universe-timeline-title",
    "name": "reality-universe-timeline",
    "title": "⏳ Timeline of Everything",
    "description": "From the Big Bang to the heat death of the universe. Slide through 13.8 billion years of cosmic history and see how reality unfolded.",
    "category": "Science & Engineering",
    "file": "reality-universe-timeline.html",
    "path": "cards/reality-universe-timeline.html"
  },
  {
    "id": "reality-what-is-consciousness-title",
    "name": "reality-what-is-consciousness",
    "title": "🧠 What Is Consciousness?",
    "description": "The hardest problem in science. Explore the mystery of subjective experience — how does matter become aware? Interactive exploration of the leading theories.",
    "category": "Science & Engineering",
    "file": "reality-what-is-consciousness.html",
    "path": "cards/reality-what-is-consciousness.html"
  },
  {
    "id": "reality-why-something-rather-than-nothing-title",
    "name": "reality-why-something-rather-than-nothing",
    "title": "🕳️ Why Is There Something Rather Than Nothing?",
    "description": "The deepest question philosophy has ever asked. Explore the mystery of existence itself — why does anything exist at all?",
    "category": "Science & Engineering",
    "file": "reality-why-something-rather-than-nothing.html",
    "path": "cards/reality-why-something-rather-than-nothing.html"
  },
  {
    "id": "recipeconverter-title",
    "name": "recipeconverter",
    "title": "🍳 Recipe Converter",
    "description": "Scale recipes, convert measurements, and adjust serving sizes. Supports metric, imperial, cups, spoons.",
    "category": "Culinary & Food Science",
    "file": "recipeconverter.html",
    "path": "cards/recipeconverter.html"
  },
  {
    "id": "recording-basics-title",
    "name": "recording-basics",
    "title": "🎤 Recording Basics",
    "description": "Learn fundamental recording techniques. ⚠️ Educational only — always verify with professional resources.",
    "category": "Music & Audio",
    "file": "recording-basics.html",
    "path": "cards/recording-basics.html"
  },
  {
    "id": "recursion-memoization-explorer-title",
    "name": "recursion-memoization-explorer",
    "title": "🌳 Recursion & Memoization Explorer",
    "description": "The same Fibonacci function, two ways: naive recursion recomputes the same subproblems a staggering number of times, while memoization remembers each answer once. Watch the call tree fill with dupl...",
    "category": "Algorithms & Computer Science",
    "file": "recursion-memoization-explorer.html",
    "path": "cards/recursion-memoization-explorer.html"
  },
  {
    "id": "redshift-distance-calculator-title",
    "name": "redshift-distance-calculator",
    "title": "🔴 Redshift & Cosmic Distance",
    "description": "Put in a redshift and get the recession velocity, Hubble distance, light-travel time and the wavelength a known spectral line is shifted to. Distinguishes Doppler motion from cosmological expansion.",
    "category": "Astronomy & Space",
    "file": "redshift-distance-calculator.html",
    "path": "cards/redshift-distance-calculator.html"
  },
  {
    "id": "redundancy-notice-calculator-title",
    "name": "redundancy-notice-calculator",
    "title": "📋 Redundancy & Notice Entitlement Calculator",
    "description": "Work out your UK statutory redundancy pay, notice period, accrued holiday and how much of a settlement is tax-free — with the full age-banded breakdown, year by year. Nothing you enter leaves your ...",
    "category": "Finance & Money",
    "file": "redundancy-notice-calculator.html",
    "path": "cards/redundancy-notice-calculator.html"
  },
  {
    "id": "regex-cheat-sheet-title",
    "name": "regex-cheat-sheet",
    "title": "🔍 Regex Cheat Sheet & Tester",
    "description": "Complete regex reference with live testing. Pattern syntax, flags, character classes, quantifiers, and groups — all in one place.",
    "category": "Algorithms & Computer Science",
    "file": "regex-cheat-sheet.html",
    "path": "cards/regex-cheat-sheet.html"
  },
  {
    "id": "regex-replace-string-transform-title",
    "name": "regex-replace-string-transform",
    "title": "⚡ Regex Transform Studio",
    "description": "Search, replace, extract capture groups, and batch-transform text with real-time regular expression pattern matching.",
    "category": "Writing & Language",
    "file": "regex-replace-string-transform.html",
    "path": "cards/regex-replace-string-transform.html"
  },
  {
    "id": "regex-tester-explainer-title",
    "name": "regex-tester-explainer",
    "title": "⚡ Regex Tester & Explainer",
    "description": "Test, debug, and understand regular expressions in real-time. Features live match highlighting, capture group extraction, and a built-in library of common production patterns.",
    "category": "Writing & Language",
    "file": "regex-tester-explainer.html",
    "path": "cards/regex-tester-explainer.html"
  },
  {
    "id": "reminder-title",
    "name": "reminder",
    "title": "⏰ Reminder Tool",
    "description": "Create reminders that stay saved in your browser. Works offline — data saved locally.",
    "category": "Productivity & Lifestyle",
    "file": "reminder.html",
    "path": "cards/reminder.html"
  },
  {
    "id": "rent-title",
    "name": "rent",
    "title": "🏠 Rent Calculator",
    "description": "Split rent among roommates, calculate per-person costs, and account for room size differences. Supports multiple currencies and custom splits.",
    "category": "Finance & Money",
    "file": "rent.html",
    "path": "cards/rent.html"
  },
  {
    "id": "rental-yield-calculator-title",
    "name": "rental-yield-calculator",
    "title": "🔑 Rental Yield Calculator",
    "description": "Gross yield is annual rent ÷ purchase price. Net yield subtracts the yearly costs you type. A listing’s “yield” is often gross. This is a ratio, not investment advice.",
    "category": "Finance & Money",
    "file": "rental-yield-calculator.html",
    "path": "cards/rental-yield-calculator.html"
  },
  {
    "id": "rental-yield-deal-analyser-title",
    "name": "rental-yield-deal-analyser",
    "title": "🏠 Rental Yield Deal Analyser",
    "description": "Compare gross yield, net yield and monthly cash flow for a prospective rental property. All calculations stay in your browser.",
    "category": "Finance & Money",
    "file": "rental-yield-deal-analyser.html",
    "path": "cards/rental-yield-deal-analyser.html"
  },
  {
    "id": "resistor-color-code-title",
    "name": "resistor-color-code",
    "title": "🎨 Resistor Color Code",
    "description": "Decode resistor color bands into resistance values. ⚠️ Educational only — verify with multimeter.",
    "category": "Science & Engineering",
    "file": "resistor-color-code.html",
    "path": "cards/resistor-color-code.html"
  },
  {
    "id": "resume-title",
    "name": "resume",
    "title": "📄 Resume Builder",
    "description": "Create and preview a professional resume. Generates clean, printable format.",
    "category": "Writing & Language",
    "file": "resume.html",
    "path": "cards/resume.html"
  },
  {
    "id": "retainer-capacity-planner-title",
    "name": "retainer-capacity-planner",
    "title": "⏱️ Retainer Capacity Planner",
    "description": "Check whether monthly client retainers fit your available hours and reveal effective revenue per hour. All calculations stay in your browser.",
    "category": "SaaS & Business Killers",
    "file": "retainer-capacity-planner.html",
    "path": "cards/retainer-capacity-planner.html"
  },
  {
    "id": "retirement-title",
    "name": "retirement",
    "title": "💰 Retirement Calculator",
    "description": "Estimate your retirement savings growth with compound interest. ⚠️ Educational only — consult a financial advisor.",
    "category": "Finance & Money",
    "file": "retirement.html",
    "path": "cards/retirement.html"
  },
  {
    "id": "reward-site-reality-check-title",
    "name": "reward-site-reality-check",
    "title": "💸 Reward Site Earnings Reality Check",
    "description": "Work out what survey and get-paid-to sites are actually worth per hour before you give them your evenings. Uses realistic rate bands rather than the &ldquo;earn &pound;500 a month from your sofa&rd...",
    "category": "Finance & Money",
    "file": "reward-site-reality-check.html",
    "path": "cards/reward-site-reality-check.html"
  },
  {
    "id": "rf-link-budget-fresnel-planner-title",
    "name": "rf-link-budget-fresnel-planner",
    "title": "📡 RF Link Budget & Fresnel Zone Planner",
    "description": "Will the link work? Radio needs more than line of sight — it needs a clear ellipse of space around the beam, and the Earth quietly bulges up into it. This adds up every gain and loss in the chain, ...",
    "category": "Science & Engineering",
    "file": "rf-link-budget-fresnel-planner.html",
    "path": "cards/rf-link-budget-fresnel-planner.html"
  },
  {
    "id": "rhyme-finder-title",
    "name": "rhyme-finder",
    "title": "🪞 Rhyme Finder",
    "description": "Find true rhymes and near rhymes for any word — powered by an embedded CMU pronunciation dictionary, no network needed.",
    "category": "Writing & Language",
    "file": "rhyme-finder.html",
    "path": "cards/rhyme-finder.html"
  },
  {
    "id": "rhythm-generator-title",
    "name": "rhythm-generator",
    "title": "🥁 Rhythm Generator",
    "description": "Generate rhythm patterns for practice and composition. ⚠️ Educational only — verify with professional resources.",
    "category": "Music & Audio",
    "file": "rhythm-generator.html",
    "path": "cards/rhythm-generator.html"
  },
  {
    "id": "rice-water-ratio-calculator-title",
    "name": "rice-water-ratio-calculator",
    "title": "🍚 Rice-to-Water Ratio Calculator",
    "description": "Absorption method volumes. Rinse until the water runs clearer; aged basmati wants a little more water; brown rice needs time, not only liquid. A rice cooker may want its own cup marks.",
    "category": "Culinary & Food Science",
    "file": "rice-water-ratio-calculator.html",
    "path": "cards/rice-water-ratio-calculator.html"
  },
  {
    "id": "riley-goblin-smasher-title",
    "name": "riley-goblin-smasher",
    "title": "🧙 Riley: Goblin Smasher",
    "description": "Procedural platformer with wave-based combat. Play as Riley the wizard, smash goblins with fireballs, dash through levels!",
    "category": "Mind-Blowing Demos",
    "file": "riley-goblin-smasher.html",
    "path": "cards/riley-goblin-smasher.html"
  },
  {
    "id": "ring-size-converter-title",
    "name": "ring-size-converter",
    "title": "💍 Ring Size Converter",
    "description": "Convert UK letters, US numbers, EU/ISO circumference and inner diameter. Based on a circular inside; wide bands often need a half-size up. Measure a well-fitting ring, not a string if you can help it.",
    "category": "Productivity & Lifestyle",
    "file": "ring-size-converter.html",
    "path": "cards/ring-size-converter.html"
  },
  {
    "id": "river-meander-lab-title",
    "name": "river-meander-lab",
    "title": "🏞️ River Meander Lab",
    "description": "A free channel migrates by the Ikeda–Parker–Sawai law: banks erode on the outside of a bend and deposit on the inside. Raise discharge and the bends fatten; raise cohesion and they freeze. When a n...",
    "category": "Interactive Art & Living Worlds",
    "file": "river-meander-lab.html",
    "path": "cards/river-meander-lab.html"
  },
  {
    "id": "robots-sitemap-generator-title",
    "name": "robots-sitemap-generator",
    "title": "🗺️ Robots.txt & Sitemap Generator",
    "description": "Draft a valid robots.txt and XML sitemap from your own URL list. Add paths or full URLs, set crawl rules and download the result. This is a local generator, not a crawler: it never visits or upload...",
    "category": "SaaS & Business Killers",
    "file": "robots-sitemap-generator.html",
    "path": "cards/robots-sitemap-generator.html"
  },
  {
    "id": "rock-cycle-mineral-id-lab-title",
    "name": "rock-cycle-mineral-id-lab",
    "title": "🪨 Rock Cycle & Mineral ID Lab",
    "description": "Two ways to learn geology hands-on: drive a rock through the full cycle (weather it, bury it, metamorphose it, melt it) with real pressure–temperature conditions and metamorphic facies, then play M...",
    "category": "Interactive Art & Living Worlds",
    "file": "rock-cycle-mineral-id-lab.html",
    "path": "cards/rock-cycle-mineral-id-lab.html"
  },
  {
    "id": "roi-title",
    "name": "roi",
    "title": "📈 ROI Calculator",
    "description": "Calculate Return on Investment with advanced metrics and comparisons. Supports annualized returns and multiple currencies.",
    "category": "Finance & Money",
    "file": "roi.html",
    "path": "cards/roi.html"
  },
  {
    "id": "roman-coin-denominations-title",
    "name": "roman-coin-denominations",
    "title": "🪙 The Coin Room",
    "description": "Early Imperial bronze and silver, counted in asses. 4 asses = 1 sestertius; 4 sestertii = 1 denarius; 25 denarii = 1 aureus. A legionary under Augustus took 225 denarii a year (before stoppages). E...",
    "category": "Museum & Collection",
    "file": "roman-coin-denominations.html",
    "path": "cards/roman-coin-denominations.html"
  },
  {
    "id": "roman-numeral-converter-title",
    "name": "roman-numeral-converter",
    "title": "🏛️ Roman Numeral Converter",
    "description": "Convert numbers to Roman numerals and back, with a step-by-step breakdown of how each numeral is built. Handles 1–3,999 in standard notation and up to 3,999,999 with overline (vinculum) notation. I...",
    "category": "Mathematics",
    "file": "roman-numeral-converter.html",
    "path": "cards/roman-numeral-converter.html"
  },
  {
    "id": "roman-numeral-number-converter-title",
    "name": "roman-numeral-number-converter",
    "title": "🏛️ Roman Numeral & Number Base Converter",
    "description": "Convert any number to Roman numerals (with overline notation for 4,000+), binary, octal, hexadecimal, base-36, words, ordinal and scientific form — or type a Roman numeral, binary or hex value and ...",
    "category": "Mathematics",
    "file": "roman-numeral-number-converter.html",
    "path": "cards/roman-numeral-number-converter.html"
  },
  {
    "id": "roof-pitch-rafter-calculator-title",
    "name": "roof-pitch-rafter-calculator",
    "title": "🏠 Roof Pitch & Rafter Calculator",
    "description": "Roof pitch is the rise in inches for every 12\" of run. Enter the pitch and half-span (run), and get the rafter length, angle and roof-area multiplier.",
    "category": "Home & DIY",
    "file": "roof-pitch-rafter-calculator.html",
    "path": "cards/roof-pitch-rafter-calculator.html"
  },
  {
    "id": "room-acoustics-simulator-title",
    "name": "room-acoustics-simulator",
    "title": "🔊 The Echo Chamber",
    "description": "Watch sound bounce around a room in real time. See wavefronts propagate from a source, reflect off walls, and decay as materials absorb their energy. Adjust room size, wall material, and source pos...",
    "category": "Museum & Collection",
    "file": "room-acoustics-simulator.html",
    "path": "cards/room-acoustics-simulator.html"
  },
  {
    "id": "room-btu-hvac-calculator-title",
    "name": "room-btu-hvac-calculator",
    "title": "🌡️ Room BTU & HVAC Sizing Calculator",
    "description": "Estimate the heating and cooling load for a room: area, ceiling height, insulation, sun exposure, occupancy and climate all move the number of BTUs you need.",
    "category": "Home & DIY",
    "file": "room-btu-hvac-calculator.html",
    "path": "cards/room-btu-hvac-calculator.html"
  },
  {
    "id": "room-layout-planner-title",
    "name": "room-layout-planner",
    "title": "🛋️ Room Layout Planner",
    "description": "Drag and drop furniture to plan your room layout. Scale-accurate 2D top-down view.",
    "category": "Home & DIY",
    "file": "room-layout-planner.html",
    "path": "cards/room-layout-planner.html"
  },
  {
    "id": "round-robin-fixture-generator-title",
    "name": "round-robin-fixture-generator",
    "title": "📅 Round-Robin Fixture Generator",
    "description": "Generate a full league schedule where every team plays every other team — once, or twice home and away. The circle method guarantees no team plays twice in a round, and odd numbers get a bye.",
    "category": "Sports",
    "file": "round-robin-fixture-generator.html",
    "path": "cards/round-robin-fixture-generator.html"
  },
  {
    "id": "rounding-estimation-trainer-title",
    "name": "rounding-estimation-trainer",
    "title": "🔄 Rounding & Estimation Trainer",
    "description": "Master rounding rules and quick estimation. Round any number to a chosen place, then estimate answers to real-life word problems with 5-round quizzes and full working.",
    "category": "Mathematics",
    "file": "rounding-estimation-trainer.html",
    "path": "cards/rounding-estimation-trainer.html"
  },
  {
    "id": "rowing-erg-pace-calculator-title",
    "name": "rowing-erg-pace-calculator",
    "title": "🚣 Rowing Erg Pace Calculator",
    "description": "The rowing machine's watts and your 500 m split are two ways of saying the same thing. Enter either and this works out the other, plus your speed and predicted times for the standard test distances.",
    "category": "Sports",
    "file": "rowing-erg-pace-calculator.html",
    "path": "cards/rowing-erg-pace-calculator.html"
  },
  {
    "id": "rugby-points-score-builder-title",
    "name": "rugby-points-score-builder",
    "title": "🏉 Rugby Points Score Builder",
    "description": "Try 5, conversion 2, penalty 3, drop goal 3. Add up a score, or work backwards: give a points gap and this lists every combination of tries, conversions, penalties and drop goals that closes it — f...",
    "category": "Sports",
    "file": "rugby-points-score-builder.html",
    "path": "cards/rugby-points-score-builder.html"
  },
  {
    "id": "rule-of-72-doubling-calculator-title",
    "name": "rule-of-72-doubling-calculator",
    "title": "⏳ Rule of 72 Doubling Time",
    "description": "Years to double ≈ 72 ÷ annual %. At 6% that’s about 12 years; at 9% about 8. The exact figure is ln(2)/ln(1+r). A back-of-envelope for interest, inflation and population — not a guarantee.",
    "category": "Finance & Money",
    "file": "rule-of-72-doubling-calculator.html",
    "path": "cards/rule-of-72-doubling-calculator.html"
  },
  {
    "id": "running-cadence-stride-calculator-title",
    "name": "running-cadence-stride-calculator",
    "title": "🏃 Running Cadence & Stride Length",
    "description": "Cadence, pace and stride length are locked together — fix any two and the third is forced. Fill in the two you know and this computes the rest, plus your steps per kilometre and total steps for a d...",
    "category": "Sports",
    "file": "running-cadence-stride-calculator.html",
    "path": "cards/running-cadence-stride-calculator.html"
  },
  {
    "id": "running-split-pace-calculator-title",
    "name": "running-split-pace-calculator",
    "title": "🏃 Running Split Pace Calculator",
    "description": "Target time for a race distance → pace per km and per mile, plus even kilometre splits. Negative splits are a planning aid, not a training plan.",
    "category": "Sports",
    "file": "running-split-pace-calculator.html",
    "path": "cards/running-split-pace-calculator.html"
  },
  {
    "id": "saas-churn-revenue-impact-title",
    "name": "saas-churn-revenue-impact",
    "title": "📉 SaaS Churn Revenue Impact",
    "description": "Model recurring revenue lost to churn and the customers needed to maintain or grow monthly revenue. All calculations stay in your browser.",
    "category": "SaaS & Business Killers",
    "file": "saas-churn-revenue-impact.html",
    "path": "cards/saas-churn-revenue-impact.html"
  },
  {
    "id": "saas-metrics-ltv-cac-calculator-title",
    "name": "saas-metrics-ltv-cac-calculator",
    "title": "📈 SaaS LTV & CAC Calculator",
    "description": "Calculate core SaaS unit economics, Customer Lifetime Value (LTV), Customer Acquisition Cost (CAC), payback period, and cash burn runway. Replaces expensive subscription analytics dashboards.",
    "category": "SaaS & Business Killers",
    "file": "saas-metrics-ltv-cac-calculator.html",
    "path": "cards/saas-metrics-ltv-cac-calculator.html"
  },
  {
    "id": "salary-title",
    "name": "salary",
    "title": "💰 Salary Calculator",
    "description": "Calculate net salary after taxes, deductions, and contributions. ⚠️ Estimates only — consult a tax professional.",
    "category": "Finance & Money",
    "file": "salary.html",
    "path": "cards/salary.html"
  },
  {
    "id": "salarycompare-title",
    "name": "salarycompare",
    "title": "🧾 Take-Home Pay Breakdown",
    "description": "Turn an annual salary into what actually lands in your account, broken down by pay period. Uses 2024/25-style UK income tax bands, Class 1 National Insurance and a student loan plan of your choice.",
    "category": "Finance & Money",
    "file": "salarycompare.html",
    "path": "cards/salarycompare.html"
  },
  {
    "id": "sales-commission-calculator-title",
    "name": "sales-commission-calculator",
    "title": "💼 Sales Commission Calculator",
    "description": "Commission from a sale amount and rate, with an optional second-tier rate above a threshold (common in sales plans). Gross figures — tax is not deducted.",
    "category": "Finance & Money",
    "file": "sales-commission-calculator.html",
    "path": "cards/sales-commission-calculator.html"
  },
  {
    "id": "sand-dune-lab-title",
    "name": "sand-dune-lab",
    "title": "🏜️ Sand Dune Lab",
    "description": "A saltation cellular automaton of a sand sea. Wind above Bagnold's threshold picks up grains, slip faces (34°) trap them, vegetation anchors the sand, and supply + wind variability decide whether b...",
    "category": "Interactive Art & Living Worlds",
    "file": "sand-dune-lab.html",
    "path": "cards/sand-dune-lab.html"
  },
  {
    "id": "sandpile-fractal-mandala-zen-title",
    "name": "sandpile-fractal-mandala-zen",
    "title": "⏳ Sandpile Mandala",
    "description": "An emergent self-organized criticality simulator. Drop grains of sand into an abelian lattice. When cells exceed four grains, they topple into cascading avalanches, spontaneously forming hyper-comp...",
    "category": "Interactive Art & Living Worlds",
    "file": "sandpile-fractal-mandala-zen.html",
    "path": "cards/sandpile-fractal-mandala-zen.html"
  },
  {
    "id": "savings-title",
    "name": "savings",
    "title": "💰 Savings Calculator",
    "description": "Calculate how much your savings will grow with regular deposits and compound interest.",
    "category": "Finance & Money",
    "file": "savings.html",
    "path": "cards/savings.html"
  },
  {
    "id": "scale-trainer-title",
    "name": "scale-trainer",
    "title": "🎹 Scale Trainer",
    "description": "Practice scales in different keys. Educational only — always verify with a music teacher or professional resource.",
    "category": "Music & Audio",
    "file": "scale-trainer.html",
    "path": "cards/scale-trainer.html"
  },
  {
    "id": "scam-sense-checker-title",
    "name": "scam-sense-checker",
    "title": "🛡️ Scam Sense Checker",
    "description": "Paste a text, email or message and see which warning signs it contains. Everything is analysed on your own device — the message is never uploaded, which matters because pasting a scam into a websit...",
    "category": "Wellbeing & Community",
    "file": "scam-sense-checker.html",
    "path": "cards/scam-sense-checker.html"
  },
  {
    "id": "schengen-90-180-day-calculator-title",
    "name": "schengen-90-180-day-calculator",
    "title": "🇪🇺 Schengen 90/180 Calculator",
    "description": "Short-stay visitors can spend 90 days in any rolling 180-day window in the Schengen area (unless a visa or residence permit says otherwise). Add trips; days of entry and exit both count. Not immigr...",
    "category": "Productivity & Lifestyle",
    "file": "schengen-90-180-day-calculator.html",
    "path": "cards/schengen-90-180-day-calculator.html"
  },
  {
    "id": "schlier-flow-thermal-shadow-title",
    "name": "schlier-flow-thermal-shadow",
    "title": "🔥 Schlieren Optics Airflow",
    "description": "August Toepler's 1864 Schlieren photography system. Visualizes invisible thermal convection plumes and supersonic shockwaves via refractive index gradients.",
    "category": "Science & Engineering",
    "file": "schlier-flow-thermal-shadow.html",
    "path": "cards/schlier-flow-thermal-shadow.html"
  },
  {
    "id": "science-quiz-title",
    "name": "science-quiz",
    "title": "Science Quiz Generator",
    "description": "Generate science quiz questions and test your knowledge with fun facts.",
    "category": "Science & Engineering",
    "file": "science-quiz.html",
    "path": "cards/science-quiz.html"
  },
  {
    "id": "science-title",
    "name": "science",
    "title": "🔬 Science Study List",
    "description": "Build your science study list. Add topics and notes, then test yourself by hiding the notes. Saved locally in your browser.",
    "category": "Science & Engineering",
    "file": "science.html",
    "path": "cards/science.html"
  },
  {
    "id": "scientific-calculator-title",
    "name": "scientific-calculator",
    "title": "🧮 Scientific Calculator",
    "description": "Full-featured scientific calculator with trigonometry, logarithms, powers, and memory functions. Works offline.",
    "category": "Mathematics",
    "file": "scientific-calculator.html",
    "path": "cards/scientific-calculator.html"
  },
  {
    "id": "scientific-method-title",
    "name": "scientific-method",
    "title": "🔬 Scientific Method Helper",
    "description": "Work through the scientific method. Enter your experiment idea and generate a structured outline.",
    "category": "Science & Engineering",
    "file": "scientific-method.html",
    "path": "cards/scientific-method.html"
  },
  {
    "id": "scientific-notation-sigfig-calculator-title",
    "name": "scientific-notation-sigfig-calculator",
    "title": "🔬 Scientific Notation & Sig Figs",
    "description": "Convert a number to scientific / engineering notation and round to significant figures. 1.23 × 10⁴ is 12300. Trailing zeros in 1000 are ambiguous — say how many sig figs you want.",
    "category": "Mathematics",
    "file": "scientific-notation-sigfig-calculator.html",
    "path": "cards/scientific-notation-sigfig-calculator.html"
  },
  {
    "id": "scrabble-score-calculator-title",
    "name": "scrabble-score-calculator",
    "title": "🔤 Scrabble Score Calculator",
    "description": "English (Hasbro / Mattel) tile values. Type a word, mark double/triple letter on a character with 2 or 3 after it (C3AT = C on a TL). Word multipliers apply after letters. Bingo +50 for 7 tiles.",
    "category": "MrProphecy Arcade",
    "file": "scrabble-score-calculator.html",
    "path": "cards/scrabble-score-calculator.html"
  },
  {
    "id": "scrabble-word-score-title",
    "name": "scrabble-word-score",
    "title": "🅰️ Scrabble Word Score",
    "description": "Score any word with classic Scrabble letter values, including blank tiles, premium squares and the bonus for using all seven.",
    "category": "MrProphecy Arcade",
    "file": "scrabble-word-score.html",
    "path": "cards/scrabble-word-score.html"
  },
  {
    "id": "screen-ppi-calculator-title",
    "name": "screen-ppi-calculator",
    "title": "🖥️ Screen PPI Calculator",
    "description": "Pixels per inch from diagonal size and resolution. Also shows pixel pitch, aspect ratio and whether the display is “Retina” at a typical viewing distance (1 arc-minute).",
    "category": "Productivity & Lifestyle",
    "file": "screen-ppi-calculator.html",
    "path": "cards/screen-ppi-calculator.html"
  },
  {
    "id": "screen-ruler-pixel-measure-title",
    "name": "screen-ruler-pixel-measure",
    "title": "📏 On-Screen Ruler & Pixel-to-Physical Converter",
    "description": "Turn your screen into a ruler. Calibrate once with a bank card (85.6 mm wide) or by entering your screen's diagonal size, then measure real objects in mm, cm and inches — and convert between CSS pi...",
    "category": "Productivity & Lifestyle",
    "file": "screen-ruler-pixel-measure.html",
    "path": "cards/screen-ruler-pixel-measure.html"
  },
  {
    "id": "screen-ruler-title",
    "name": "screen-ruler",
    "title": "📏 Screen Ruler & Pixel Measure",
    "description": "Measure pixels on your screen. Drag rulers, measure distances, and get precise pixel coordinates.",
    "category": "Productivity & Lifestyle",
    "file": "screen-ruler.html",
    "path": "cards/screen-ruler.html"
  },
  {
    "id": "screw-drill-chart-title",
    "name": "screw-drill-chart",
    "title": "🔩 Screw & Drill Bit Size Chart",
    "description": "Look up the right drill bit for any screw size, wall plug colour, and pilot hole diameter. No more guessing.",
    "category": "Home & DIY",
    "file": "screw-drill-chart.html",
    "path": "cards/screw-drill-chart.html"
  },
  {
    "id": "seawater-salinity-density-teos-title",
    "name": "seawater-salinity-density-teos",
    "title": "🌊 Seawater Salinity & Density",
    "description": "Investigate ocean physics and the thermodynamic equation of seawater (TEOS-10). Calculate in-situ density ($\\rho$), freezing point depression ($-1.91^\\circ\\text{C}$), sound speed ($c$), and thermoh...",
    "category": "Science & Engineering",
    "file": "seawater-salinity-density-teos.html",
    "path": "cards/seawater-salinity-density-teos.html"
  },
  {
    "id": "second-life-surnames-guide-title",
    "name": "second-life-surnames-guide",
    "title": "📚 Second Life Surnames Encyclopedia",
    "description": "Explore the rich tapestry of Second Life surnames. Discover origins, cultural associations, and roleplay inspiration. A living encyclopedia with search, filters, and favorite tracking.",
    "category": "Virtual Worlds & Gaming",
    "file": "second-life-surnames-guide.html",
    "path": "cards/second-life-surnames-guide.html"
  },
  {
    "id": "secret-santa-title",
    "name": "secret-santa",
    "title": "🎁 Secret Santa Generator",
    "description": "Organize a perfect Secret Santa gift exchange with automatic matching, restrictions, and wish lists! ✅ Supports: Family restrictions, wish lists, budget tracking, email notifications",
    "category": "Productivity & Lifestyle",
    "file": "secret-santa.html",
    "path": "cards/secret-santa.html"
  },
  {
    "id": "seed-germination-calculator-title",
    "name": "seed-germination-calculator",
    "title": "🌱 Seed Germination Calculator",
    "description": "Predict germination time based on seed type, temperature, and environmental factors using USDA, UC Davis, and university research data. This tool is supported by user contributions .",
    "category": "Science & Engineering",
    "file": "seed-germination-calculator.html",
    "path": "cards/seed-germination-calculator.html"
  },
  {
    "id": "semver-compare-bump-calculator-title",
    "name": "semver-compare-bump-calculator",
    "title": "📦 SemVer Compare & Bump",
    "description": "Compare two Semantic Versioning 2.0.0 strings, then bump major, minor, patch or a pre-release. Precedence follows the spec: major.minor.patch, then pre-release identifiers, build metadata ignored.",
    "category": "Algorithms & Computer Science",
    "file": "semver-compare-bump-calculator.html",
    "path": "cards/semver-compare-bump-calculator.html"
  },
  {
    "id": "seo-helper-title",
    "name": "seo-helper",
    "title": "🔍 SEO & Content Optimizer",
    "description": "Professional SEO analysis, optimization, and content planning. Get actionable insights and comprehensive reports.",
    "category": "Writing & Language",
    "file": "seo-helper.html",
    "path": "cards/seo-helper.html"
  },
  {
    "id": "seo-meta-tag-social-previewer-title",
    "name": "seo-meta-tag-social-previewer",
    "title": "🔍 SEO Meta Tag Previewer",
    "description": "Generate and preview Open Graph, Twitter Cards, and SEO meta tags in real time. Simulate Google SERP snippets and social media feed cards before deploying. Replaces expensive monthly SEO subscripti...",
    "category": "SaaS & Business Killers",
    "file": "seo-meta-tag-social-previewer.html",
    "path": "cards/seo-meta-tag-social-previewer.html"
  },
  {
    "id": "seo-writing-title",
    "name": "seo-writing",
    "title": "✍️ SEO Writing Assistant",
    "description": "Optimize text for search engines. Paste your draft, choose focus keywords, and get suggestions for keyword density, headings, meta description, and readability improvements.",
    "category": "Writing & Language",
    "file": "seo-writing.html",
    "path": "cards/seo-writing.html"
  },
  {
    "id": "sequences-series-title",
    "name": "sequences-series",
    "title": "🔢 Sequences & Series Calculator",
    "description": "Find any term and the running sum of arithmetic or geometric sequences, test a geometric series for convergence, and see the working for the formula you used.",
    "category": "Mathematics",
    "file": "sequences-series.html",
    "path": "cards/sequences-series.html"
  },
  {
    "id": "seven-wonders-hall-title",
    "name": "seven-wonders-hall",
    "title": "🏺 The Seven Wonders",
    "description": "A Hellenistic tourist list, not a league table. Antipater of Sidon and others named seven sights a traveller from the Mediterranean might still catch. Only the Great Pyramid is still standing. The ...",
    "category": "Museum & Collection",
    "file": "seven-wonders-hall.html",
    "path": "cards/seven-wonders-hall.html"
  },
  {
    "id": "sheet-music-title",
    "name": "sheet-music",
    "title": "🎼 Sheet Music Reference Generator",
    "description": "Generate detailed sheet music references with proper notation guidance. ⚠️ Educational only — always verify with a teacher or professional resource.",
    "category": "Music & Audio",
    "file": "sheet-music.html",
    "path": "cards/sheet-music.html"
  },
  {
    "id": "shelf-bracket-calculator-title",
    "name": "shelf-bracket-calculator",
    "title": "📏 Shelf Bracket Calculator",
    "description": "Calculate the right bracket size, spacing, and load capacity for your shelf project.",
    "category": "Home & DIY",
    "file": "shelf-bracket-calculator.html",
    "path": "cards/shelf-bracket-calculator.html"
  },
  {
    "id": "shift-labour-cost-planner-title",
    "name": "shift-labour-cost-planner",
    "title": "🗓️ Shift Labour Cost Planner",
    "description": "Price a staffed shift including breaks, employer on-costs and overtime before publishing the rota. All calculations stay in your browser.",
    "category": "Interactive Art & Living Worlds",
    "file": "shift-labour-cost-planner.html",
    "path": "cards/shift-labour-cost-planner.html"
  },
  {
    "id": "shoe-size-converter-title",
    "name": "shoe-size-converter",
    "title": "👟 Shoe Size Converter",
    "description": "Convert adult shoe sizes between US, UK, EU and Mondopoint (mm). Based on standard last-length charts — brands still vary by a half size, so treat this as a starting point, not a fitting.",
    "category": "Productivity & Lifestyle",
    "file": "shoe-size-converter.html",
    "path": "cards/shoe-size-converter.html"
  },
  {
    "id": "shoppinglist-title",
    "name": "shoppinglist",
    "title": "🛒 Smart Shopping List",
    "description": "Add items, organize by category, track quantities, and manage your shopping efficiently. ✅ Features: Categories, quantity tracking, budget calculator, shareable lists",
    "category": "Productivity & Lifestyle",
    "file": "shoppinglist.html",
    "path": "cards/shoppinglist.html"
  },
  {
    "id": "showjumping-faults-calculator-title",
    "name": "showjumping-faults-calculator",
    "title": "🐎 Showjumping Faults Calculator",
    "description": "Faults add up fast: 4 for a knockdown, 4 for a refusal, and 1 for every second over the time allowed. Enter a round and get the total, then use a rival's faults and time to settle a jump-off.",
    "category": "Sports",
    "file": "showjumping-faults-calculator.html",
    "path": "cards/showjumping-faults-calculator.html"
  },
  {
    "id": "skip-hire-volume-calculator-title",
    "name": "skip-hire-volume-calculator",
    "title": "🗑️ Skip Hire Volume Calculator",
    "description": "Rough cubic yards from room waste, rubble or bags. UK skips are sold in yards: 4, 6, 8, 12, 16. Loose waste settles; rubble is heavy — many yards cap weight before the skip looks full. Not a quote.",
    "category": "Home & DIY",
    "file": "skip-hire-volume-calculator.html",
    "path": "cards/skip-hire-volume-calculator.html"
  },
  {
    "id": "sl-avatar-height-calculator-title",
    "name": "sl-avatar-height-calculator",
    "title": "📏 SL Avatar Height & Proportion Calculator",
    "description": "Calculate your avatar's true height, body proportions, and get recommendations for realistic or stylized looks",
    "category": "Virtual Worlds & Gaming",
    "file": "sl-avatar-height-calculator.html",
    "path": "cards/sl-avatar-height-calculator.html"
  },
  {
    "id": "sl-buildmate-title",
    "name": "sl-buildmate",
    "title": "🏗️ Second Life Builder's Mate",
    "description": "Professional toolkit for Second Life builders: prim allowance, object sizing, weight calculation, grid alignment, and LOD optimization. ✅ Features: Prim/LI calculation, mesh optimization, physics a...",
    "category": "Virtual Worlds & Gaming",
    "file": "sl-buildmate.html",
    "path": "cards/sl-buildmate.html"
  },
  {
    "id": "sl-events-title",
    "name": "sl-events",
    "title": "📅 Live Second Life Events",
    "description": "🟢 LIVE Real-time events from Second Life. Updates automatically.",
    "category": "Virtual Worlds & Gaming",
    "file": "sl-events.html",
    "path": "cards/sl-events.html"
  },
  {
    "id": "sl-exchange-title",
    "name": "sl-exchange",
    "title": "💰 Linden Dollar Exchange",
    "description": "Convert Linden Dollars (Second Life virtual currency) to real-world currencies using market rates. Rates are estimates — actual exchange rates may vary.",
    "category": "Virtual Worlds & Gaming",
    "file": "sl-exchange.html",
    "path": "cards/sl-exchange.html"
  },
  {
    "id": "sl-group-slot-calculator-title",
    "name": "sl-group-slot-calculator",
    "title": "👥 SL Group Slot Calculator",
    "description": "Track your group memberships — manage the 42-group limit and plan which groups to keep or drop",
    "category": "Virtual Worlds & Gaming",
    "file": "sl-group-slot-calculator.html",
    "path": "cards/sl-group-slot-calculator.html"
  },
  {
    "id": "sl-land-tier-calculator-title",
    "name": "sl-land-tier-calculator",
    "title": "🏠 SL Land Tier Calculator",
    "description": "Calculate monthly tier costs, prim budgets, and land area — for mainland, private regions, and homesteads",
    "category": "Virtual Worlds & Gaming",
    "file": "sl-land-tier-calculator.html",
    "path": "cards/sl-land-tier-calculator.html"
  },
  {
    "id": "sl-linden-dollar-converter-title",
    "name": "sl-linden-dollar-converter",
    "title": "💵 L$ Linden Dollar Converter",
    "description": "Convert between Linden Dollars (L$) and real-world currencies — USD, GBP, EUR, JPY, AUD, CAD",
    "category": "Virtual Worlds & Gaming",
    "file": "sl-linden-dollar-converter.html",
    "path": "cards/sl-linden-dollar-converter.html"
  },
  {
    "id": "sl-lsl-script-generator-title",
    "name": "sl-lsl-script-generator",
    "title": "📜 LSL Script Generator",
    "description": "Generate ready-to-use Linden Scripting Language scripts — security, teleport, dance, auto-response, and more",
    "category": "Virtual Worlds & Gaming",
    "file": "sl-lsl-script-generator.html",
    "path": "cards/sl-lsl-script-generator.html"
  },
  {
    "id": "sl-market-title",
    "name": "sl-market",
    "title": "🛒 Second Life Marketplace Search",
    "description": "Search and browse Second Life Marketplace items. Demo data shown — in production, connect to actual Marketplace API.",
    "category": "Virtual Worlds & Gaming",
    "file": "sl-market.html",
    "path": "cards/sl-market.html"
  },
  {
    "id": "sl-mesh-upload-cost-title",
    "name": "sl-mesh-upload-cost",
    "title": "🔺 SL Mesh Upload Cost Calculator",
    "description": "Estimate Land Impact and upload cost for mesh objects — input triangle counts and physics shapes",
    "category": "Virtual Worlds & Gaming",
    "file": "sl-mesh-upload-cost.html",
    "path": "cards/sl-mesh-upload-cost.html"
  },
  {
    "id": "sl-outfit-planner-title",
    "name": "sl-outfit-planner",
    "title": "👗 SL Outfit Planner",
    "description": "Plan and organize your Second Life outfits — track body parts, clothing layers, accessories, and color coordination",
    "category": "Virtual Worlds & Gaming",
    "file": "sl-outfit-planner.html",
    "path": "cards/sl-outfit-planner.html"
  },
  {
    "id": "sl-prim-budget-planner-title",
    "name": "sl-prim-budget-planner",
    "title": "🧱 SL Prim Budget Planner",
    "description": "Plan your land's prim usage — add objects, track LI (Land Impact), and stay within your budget",
    "category": "Virtual Worlds & Gaming",
    "file": "sl-prim-budget-planner.html",
    "path": "cards/sl-prim-budget-planner.html"
  },
  {
    "id": "sl-region-map-title",
    "name": "sl-region-map",
    "title": "🗺️ Second Life Region Map",
    "description": "View Second Life region maps with interactive pan/zoom, coordinates, and debugging tools. Uses multiple data sources with automatic fallback.",
    "category": "Virtual Worlds & Gaming",
    "file": "sl-region-map.html",
    "path": "cards/sl-region-map.html"
  },
  {
    "id": "sl-teleport-planner-title",
    "name": "sl-teleport-planner",
    "title": "🌀 SL Teleport & SLURL Planner",
    "description": "Build teleport notecards, generate SLURLs, and plan region visits with coordinate calculations",
    "category": "Virtual Worlds & Gaming",
    "file": "sl-teleport-planner.html",
    "path": "cards/sl-teleport-planner.html"
  },
  {
    "id": "sl-texture-cost-calculator-title",
    "name": "sl-texture-cost-calculator",
    "title": "🖼️ SL Texture Upload Cost Calculator",
    "description": "Calculate upload costs, memory usage, and get recommendations for optimal texture sizes in Second Life",
    "category": "Virtual Worlds & Gaming",
    "file": "sl-texture-cost-calculator.html",
    "path": "cards/sl-texture-cost-calculator.html"
  },
  {
    "id": "sl-texture-title",
    "name": "sl-texture",
    "title": "🖼️ Second Life Texture Tool",
    "description": "Calculate texture repeats, offsets, and rotations for Second Life prims. Perfect alignment for builders and creators. Works with any texture and prim size. This site is supported by user contributi...",
    "category": "Virtual Worlds & Gaming",
    "file": "sl-texture.html",
    "path": "cards/sl-texture.html"
  },
  {
    "id": "sl-time-converter-title",
    "name": "sl-time-converter",
    "title": "🕐 SL Time Converter",
    "description": "Convert between Second Life Time (SLT/PST) and your local time — never miss an event again",
    "category": "Virtual Worlds & Gaming",
    "file": "sl-time-converter.html",
    "path": "cards/sl-time-converter.html"
  },
  {
    "id": "sleep-circadian-rem-calculator-title",
    "name": "sleep-circadian-rem-calculator",
    "title": "🌙 Sleep & REM Optimizer",
    "description": "Calculate optimal bedtimes and wake alarms based on natural 90-minute REM cycles. Wake up refreshed and eliminate morning sleep inertia.",
    "category": "Lucid Dreaming & Sleep",
    "file": "sleep-circadian-rem-calculator.html",
    "path": "cards/sleep-circadian-rem-calculator.html"
  },
  {
    "id": "sleep-debt-calculator-title",
    "name": "sleep-debt-calculator",
    "title": "😴 Sleep Debt Calculator",
    "description": "Need minus hours actually slept, summed over the week. Most adults are in the 7–9 h band; you are not. This is arithmetic, not a sleep clinic. If you stop breathing at night, talk to a GP.",
    "category": "Lucid Dreaming & Sleep",
    "file": "sleep-debt-calculator.html",
    "path": "cards/sleep-debt-calculator.html"
  },
  {
    "id": "sleep-paralysis-hypnopompic-title",
    "name": "sleep-paralysis-hypnopompic",
    "title": "🛡️ Sleep Paralysis Navigator",
    "description": "Demystify REM motor atonia. Learn how glycine and GABA temporarily paralyze skeletal muscles, and either smoothly wake up or launch directly into a vivid lucid flight.",
    "category": "Lucid Dreaming & Sleep",
    "file": "sleep-paralysis-hypnopompic.html",
    "path": "cards/sleep-paralysis-hypnopompic.html"
  },
  {
    "id": "sleep-title",
    "name": "sleep",
    "title": "🛏️ Sleep Cycle Calculator",
    "description": "Calculate optimal wake-up times based on 90-minute sleep cycles for better rest. No affiliate links - this site is supported by user contributions .",
    "category": "Health & Fitness",
    "file": "sleep.html",
    "path": "cards/sleep.html"
  },
  {
    "id": "slug-generator-title",
    "name": "slug-generator",
    "title": "🔗 Slug Generator",
    "description": "Convert any text into URL-friendly slugs. Perfect for blog posts, filenames, and SEO-friendly URLs.",
    "category": "Algorithms & Computer Science",
    "file": "slug-generator.html",
    "path": "cards/slug-generator.html"
  },
  {
    "id": "small-claims-lba-generator-title",
    "name": "small-claims-lba-generator",
    "title": "📄 Small Claims Letter Before Action Builder",
    "description": "Build a proper Letter Before Action for an unpaid debt — with statutory interest calculated to the day, a claim-fee estimate and a 14-day deadline. Then copy it into your email or post. Free, local...",
    "category": "Finance & Money",
    "file": "small-claims-lba-generator.html",
    "path": "cards/small-claims-lba-generator.html"
  },
  {
    "id": "smart-contract-gas-estimator-title",
    "name": "smart-contract-gas-estimator",
    "title": "⛽ Web3 Gas Fee Estimator",
    "description": "Compare real-time decentralized transaction fees, DEX swap overhead, and smart contract execution costs across Solana, Base, Ethereum L1, and Polygon.",
    "category": "Finance & Money",
    "file": "smart-contract-gas-estimator.html",
    "path": "cards/smart-contract-gas-estimator.html"
  },
  {
    "id": "snooker-scorer-and-snookers-title",
    "name": "snooker-scorer-and-snookers",
    "title": "🎱 Snooker Snookers-Required Calculator",
    "description": "The question every frame hinges on: can the player behind still win, and how many snookers do they need? Set the balls left on the table and the score, and this works out the points remaining, the ...",
    "category": "Sports",
    "file": "snooker-scorer-and-snookers.html",
    "path": "cards/snooker-scorer-and-snookers.html"
  },
  {
    "id": "snowflake-crystal-lab-title",
    "name": "snowflake-crystal-lab",
    "title": "❄️ Snowflake Crystal Lab",
    "description": "Grow an ice crystal from the real Nakaya diagram: temperature and supersaturation decide its habit — plates, needles, columns, sectored plates or fern-like dendrites. Vapour is consumed by the crys...",
    "category": "Interactive Art & Living Worlds",
    "file": "snowflake-crystal-lab.html",
    "path": "cards/snowflake-crystal-lab.html"
  },
  {
    "id": "social-media-image-resizer-cropper-title",
    "name": "social-media-image-resizer-cropper",
    "title": "🎨 Social Image Resizer",
    "description": "Crop and export pixel-perfect images for every social media network directly in your browser. 100% client-side HTML5 Canvas with zero server uploads, zero watermarks, and zero monthly design subscr...",
    "category": "SaaS & Business Killers",
    "file": "social-media-image-resizer-cropper.html",
    "path": "cards/social-media-image-resizer-cropper.html"
  },
  {
    "id": "social-preview-title",
    "name": "social-preview",
    "title": "🖼️ Social Preview Generator",
    "description": "Create perfectly sized Open Graph and Twitter preview images with custom branding, layouts, and auto-generated HTML meta tags.",
    "category": "Productivity & Lifestyle",
    "file": "social-preview.html",
    "path": "cards/social-preview.html"
  },
  {
    "id": "social-proof-testimonial-card-generator-title",
    "name": "social-proof-testimonial-card-generator",
    "title": "🌟 Testimonial Card Generator",
    "description": "Turn customer reviews, tweets, and testimonials into high-converting social proof cards. Generates pure zero-dependency HTML & CSS code with zero third-party tracking scripts that hurt Google PageS...",
    "category": "SaaS & Business Killers",
    "file": "social-proof-testimonial-card-generator.html",
    "path": "cards/social-proof-testimonial-card-generator.html"
  },
  {
    "id": "socratic-thinking-coach-title",
    "name": "socratic-thinking-coach",
    "title": "🏛️ Socratic Thinking Coach",
    "description": "Sharpen your reasoning: stress-test any claim with Socratic questions, steelman the other side of an argument, and learn to spot 10 classic logical fallacies with a quiz.",
    "category": "Writing & Language",
    "file": "socratic-thinking-coach.html",
    "path": "cards/socratic-thinking-coach.html"
  },
  {
    "id": "soil-ph-guide-title",
    "name": "soil-ph-guide",
    "title": "🌱 Soil & pH Guide",
    "description": "Soil pH and type determine nutrient availability and plant success. Match plants with their preferred conditions. This tool is supported by user contributions .",
    "category": "Science & Engineering",
    "file": "soil-ph-guide.html",
    "path": "cards/soil-ph-guide.html"
  },
  {
    "id": "solar-panel-calculator-title",
    "name": "solar-panel-calculator",
    "title": "☀️ Solar Panel Calculator",
    "description": "Estimate solar panel requirements for your energy needs. Educational tool only — always consult a professional installer.",
    "category": "Science & Engineering",
    "file": "solar-panel-calculator.html",
    "path": "cards/solar-panel-calculator.html"
  },
  {
    "id": "solar-system-3d-orrery-title",
    "name": "solar-system-3d-orrery",
    "title": "🪐 3D Solar System Orrery",
    "description": "A real 3D orrery of the whole solar system with true orbital mechanics — Kepler's equation is solved every frame, so Mercury visibly speeds up at perihelion and retrograde Halley's comet dives insi...",
    "category": "Astronomy & Space",
    "file": "solar-system-3d-orrery.html",
    "path": "cards/solar-system-3d-orrery.html"
  },
  {
    "id": "solar-system-simulator-title",
    "name": "solar-system-simulator",
    "title": "🌌 Solar System Simulator",
    "description": "Interactive 2D simulation of the Solar System. Adjust time speed and scale, toggle orbits and labels, click planets for details.",
    "category": "Science & Engineering",
    "file": "solar-system-simulator.html",
    "path": "cards/solar-system-simulator.html"
  },
  {
    "id": "solar-system-size-comparison-title",
    "name": "solar-system-size-comparison",
    "title": "🪐 Solar System Size Comparator",
    "description": "See the planets side by side to true relative scale, compare them by distance, day length, gravity or moons — and find out what you'd weigh on each. All the figures are built in; nothing is fetched...",
    "category": "Astronomy & Space",
    "file": "solar-system-size-comparison.html",
    "path": "cards/solar-system-size-comparison.html"
  },
  {
    "id": "song-writer-title",
    "name": "song-writer",
    "title": "🎵 Song Writer (General Advice)",
    "description": "Brainstorm song ideas, lyrics, and structure. ⚠️ Educational only — always verify with a teacher or professional resource.",
    "category": "Music & Audio",
    "file": "song-writer.html",
    "path": "cards/song-writer.html"
  },
  {
    "id": "sorting-algorithm-visualizer-title",
    "name": "sorting-algorithm-visualizer",
    "title": "📊 Sorting Algorithm Visualizer",
    "description": "Watch six classic sorting algorithms race on the same shuffled data — see exactly why O(n&sup2;) sorts crawl while merge and quick sort fly. Every comparison and swap is counted live.",
    "category": "Algorithms & Computer Science",
    "file": "sorting-algorithm-visualizer.html",
    "path": "cards/sorting-algorithm-visualizer.html"
  },
  {
    "id": "sound-decibel-calculator-title",
    "name": "sound-decibel-calculator",
    "title": "🔊 Sound Decibel Calculator",
    "description": "Calculate sound pressure level (SPL dB) drop over distance using the acoustic inverse-square law $L_2 = L_1 - 20\\log_{10}(r_2/r_1)$, acoustic pressure in Pascals, and NIOSH/OSHA safe daily exposure...",
    "category": "Science & Engineering",
    "file": "sound-decibel-calculator.html",
    "path": "cards/sound-decibel-calculator.html"
  },
  {
    "id": "sourdough-hydration-calculator-title",
    "name": "sourdough-hydration-calculator",
    "title": "🍞 Sourdough Baker's Math Lab",
    "description": "Baker's percentage formula engine for artisanal sourdough. Factors in starter hydration, flour water absorption, and ambient room temperature bulk fermentation kinetics.",
    "category": "Culinary & Food Science",
    "file": "sourdough-hydration-calculator.html",
    "path": "cards/sourdough-hydration-calculator.html"
  },
  {
    "id": "sous-vide-precision-cooker-title",
    "name": "sous-vide-precision-cooker",
    "title": "🥩 Sous Vide Time & Temperature",
    "description": "Precision immersion cooking guide based on thermal conductivity & USDA/FSIS pasteurization curves. Calculates exact bath temperatures, heating time to core, and searing parameters.",
    "category": "Culinary & Food Science",
    "file": "sous-vide-precision-cooker.html",
    "path": "cards/sous-vide-precision-cooker.html"
  },
  {
    "id": "spanish-verb-master-title",
    "name": "spanish-verb-master",
    "title": "🇪🇸 Spanish Verb Conjugator",
    "description": "Master Spanish verb conjugations, conquer the notorious Ser vs Estar dilemma (permanent essence vs temporary state), and master Por vs Para with native Spanish audio playback.",
    "category": "Writing & Language",
    "file": "spanish-verb-master.html",
    "path": "cards/spanish-verb-master.html"
  },
  {
    "id": "speaker-ohm-wiring-calculator-title",
    "name": "speaker-ohm-wiring-calculator",
    "title": "🔊 Speaker Ohm Wiring",
    "description": "Series adds ohms; parallel is the reciprocal sum. Never present an amp with a lower load than it is rated for — that is how output stages die. Passive crossovers are not modelled.",
    "category": "Science & Engineering",
    "file": "speaker-ohm-wiring-calculator.html",
    "path": "cards/speaker-ohm-wiring-calculator.html"
  },
  {
    "id": "special-relativity-calculator-title",
    "name": "special-relativity-calculator",
    "title": "🚀 Special Relativity Simulator",
    "description": "Calculate relativistic time dilation, length contraction, and kinetic energy via Einstein's Special Relativity equations. Compare spaceship crew time against stationary observer time.",
    "category": "Science & Engineering",
    "file": "special-relativity-calculator.html",
    "path": "cards/special-relativity-calculator.html"
  },
  {
    "id": "speed-distance-time-calculator-title",
    "name": "speed-distance-time-calculator",
    "title": "🚗 Speed Distance Time Calculator",
    "description": "Fill in any two of speed, distance and time; the third is calculated. Swap units without changing the physics: metres, kilometres, miles, knots, hours, minutes, seconds.",
    "category": "Mathematics",
    "file": "speed-distance-time-calculator.html",
    "path": "cards/speed-distance-time-calculator.html"
  },
  {
    "id": "speed-reading-rsvp-trainer-title",
    "name": "speed-reading-rsvp-trainer",
    "title": "⚡ Speed-Reading RSVP Trainer",
    "description": "Train your brain to read faster with rapid serial visual presentation — while absorbing fascinating true passages about science and history. Includes a comprehension quiz so speed never beats under...",
    "category": "Writing & Language",
    "file": "speed-reading-rsvp-trainer.html",
    "path": "cards/speed-reading-rsvp-trainer.html"
  },
  {
    "id": "speed-reading-trainer-title",
    "name": "speed-reading-trainer",
    "title": "⚡ Speed Reading Trainer",
    "description": "Measure your words-per-minute, then train with guided pacing where your eye is told where to look. Includes recall questions and live WPM tracking. Nothing is stored online.",
    "category": "Writing & Language",
    "file": "speed-reading-trainer.html",
    "path": "cards/speed-reading-trainer.html"
  },
  {
    "id": "spelling-check-title",
    "name": "spelling-check",
    "title": "🔍 Smart Spelling Checker",
    "description": "Advanced spelling checker using multiple open-source dictionary APIs combined for maximum accuracy. ⚠️ Requires internet connection for online dictionary checks.",
    "category": "Writing & Language",
    "file": "spelling-check.html",
    "path": "cards/spelling-check.html"
  },
  {
    "id": "sphere-cylinder-cone-volume-title",
    "name": "sphere-cylinder-cone-volume",
    "title": "⚪ Sphere, Cylinder & Cone Volume",
    "description": "V_sphere = 4/3 π r³, A = 4 π r². Cylinder π r² h. Cone (1/3) π r² h. Enter radius and height in the same units; volume comes out in those units cubed.",
    "category": "Mathematics",
    "file": "sphere-cylinder-cone-volume.html",
    "path": "cards/sphere-cylinder-cone-volume.html"
  },
  {
    "id": "splitbill-title",
    "name": "splitbill",
    "title": "🍽️ Split Bill Calculator",
    "description": "Split restaurant bills, group expenses, or shared purchases with intelligent distribution options. ✨ Perfect for dinners, trips, and group activities!",
    "category": "Finance & Money",
    "file": "splitbill.html",
    "path": "cards/splitbill.html"
  },
  {
    "id": "spontaneous-synchronization-kuramoto-title",
    "name": "spontaneous-synchronization-kuramoto",
    "title": "🔥 Firefly Kuramoto Synchronization",
    "description": "Yoshiki Kuramoto's nonlinear synchronization model. Independent bioluminescent fireflies spontaneously phase-lock into simultaneous collective pulsing.",
    "category": "Science & Engineering",
    "file": "spontaneous-synchronization-kuramoto.html",
    "path": "cards/spontaneous-synchronization-kuramoto.html"
  },
  {
    "id": "sprite-cutter-title",
    "name": "sprite-cutter",
    "title": "🎮 Sprite Sheet Studio",
    "description": "Advanced sprite sheet cutter for game developers. Slice, preview, animate, and export sprite sheets with professional tools. ✨ Supports PNG, JPG, GIF, and WebP formats",
    "category": "Productivity & Lifestyle",
    "file": "sprite-cutter.html",
    "path": "cards/sprite-cutter.html"
  },
  {
    "id": "sql-formatter-query-helper-title",
    "name": "sql-formatter-query-helper",
    "title": "🗃️ SQL Formatter & Query Helper",
    "description": "Make a dense SQL query readable without sending it to a database. This formatter understands common SELECT, INSERT, UPDATE and DELETE clauses, preserves quoted strings/comments, and can output comp...",
    "category": "SaaS & Business Killers",
    "file": "sql-formatter-query-helper.html",
    "path": "cards/sql-formatter-query-helper.html"
  },
  {
    "id": "srt-subtitle-time-shifter-title",
    "name": "srt-subtitle-time-shifter",
    "title": "🎬 SRT Subtitle Time Shifter",
    "description": "Shift every HH:MM:SS,mmm timestamp in an .srt by milliseconds (negative to go earlier). Runs in this page — files stay on your device.",
    "category": "Algorithms & Computer Science",
    "file": "srt-subtitle-time-shifter.html",
    "path": "cards/srt-subtitle-time-shifter.html"
  },
  {
    "id": "stair-stringer-calculator-title",
    "name": "stair-stringer-calculator",
    "title": "🪜 Stair Stringer Calculator",
    "description": "Size a straight staircase: enter the total rise and your preferred riser height, and get the number of steps, the tread depth, total run and the stair angle — checked against the comfortable 2&time...",
    "category": "Home & DIY",
    "file": "stair-stringer-calculator.html",
    "path": "cards/stair-stringer-calculator.html"
  },
  {
    "id": "starfield-warp-drive-title",
    "name": "starfield-warp-drive",
    "title": "🚀 Starfield Warp Drive",
    "description": "A retro warp-speed starfield with real flight feel: steer with your pointer, throttle from sublight to Warp 9, punch through hyperspace jumps, and watch the light-years stack up as famous exoplanet...",
    "category": "Mind-Blowing Demos",
    "file": "starfield-warp-drive.html",
    "path": "cards/starfield-warp-drive.html"
  },
  {
    "id": "starling-murmuration-title",
    "name": "starling-murmuration",
    "title": "🐦 Starling Murmuration",
    "description": "Reynolds boids with the three forces starlings actually use: short-range separation, local alignment, and a weaker cohesion. Click to drop a hawk — the flock folds, splits and re-forms. The ribbon ...",
    "category": "Interactive Art & Living Worlds",
    "file": "starling-murmuration.html",
    "path": "cards/starling-murmuration.html"
  },
  {
    "id": "startup-cap-table-dilution-simulator-title",
    "name": "startup-cap-table-dilution-simulator",
    "title": "📊 Cap Table & Dilution",
    "description": "Model startup equity dilution across funding rounds. Calculates Y Combinator post-money SAFEs, valuation caps, employee option pool (ESOP) expansion, and founder equity value without paying thousan...",
    "category": "SaaS & Business Killers",
    "file": "startup-cap-table-dilution-simulator.html",
    "path": "cards/startup-cap-table-dilution-simulator.html"
  },
  {
    "id": "startup-runway-burn-rate-simulator-title",
    "name": "startup-runway-burn-rate-simulator",
    "title": "🛫 Runway & Burn Simulator",
    "description": "The question that ends startups: which month does the bank account hit zero? Enter your cash, your costs and your revenue growth, and it projects 36 months forward, finds your break-even month, cal...",
    "category": "SaaS & Business Killers",
    "file": "startup-runway-burn-rate-simulator.html",
    "path": "cards/startup-runway-burn-rate-simulator.html"
  },
  {
    "id": "statistics-illusion-gallery-title",
    "name": "statistics-illusion-gallery",
    "title": "🎭 The Illusion Gallery",
    "description": "Three statistical traps you can run with your own eyes: survivorship bias (the WW2 planes), Simpson's paradox (the kidney-stone study where one treatment wins overall yet loses everywhere), and reg...",
    "category": "Museum & Collection",
    "file": "statistics-illusion-gallery.html",
    "path": "cards/statistics-illusion-gallery.html"
  },
  {
    "id": "statistics-title",
    "name": "statistics",
    "title": "📊 Statistics Calculator",
    "description": "Comprehensive statistical analysis tool with descriptive statistics, probability distributions, hypothesis testing, and data visualization. This tool is supported by user contributions .",
    "category": "Mathematics",
    "file": "statistics.html",
    "path": "cards/statistics.html"
  },
  {
    "id": "steam-tables-thermodynamics-title",
    "name": "steam-tables-thermodynamics",
    "title": "⚙️ Steam Tables Lab",
    "description": "Industrial steam table thermodynamics (IAPWS formulation). Calculate saturation pressure ($P_{sat}$), specific enthalpy ($h$), entropy ($s$), specific volume ($v$), and latent heat ($h_{fg}$) for s...",
    "category": "Science & Engineering",
    "file": "steam-tables-thermodynamics.html",
    "path": "cards/steam-tables-thermodynamics.html"
  },
  {
    "id": "steps-title",
    "name": "steps",
    "title": "🚶 Steps to Calories Converter",
    "description": "Convert steps walked to calories burned with precision. Calculate energy expenditure based on steps, weight, and walking pace. See equivalent activities and track progress toward daily goals. This ...",
    "category": "Health & Fitness",
    "file": "steps.html",
    "path": "cards/steps.html"
  },
  {
    "id": "stone-pounds-kg-weight-converter-title",
    "name": "stone-pounds-kg-weight-converter",
    "title": "⚖️ Stone, Pounds ⇄ kg",
    "description": "Convert body weight between stone & pounds, pounds, kilograms and grams. One stone is 14 lb; one avoirdupois pound is exactly 0.45359237 kg.",
    "category": "Science & Engineering",
    "file": "stone-pounds-kg-weight-converter.html",
    "path": "cards/stone-pounds-kg-weight-converter.html"
  },
  {
    "id": "stopwatch-lap-interval-timer-title",
    "name": "stopwatch-lap-interval-timer",
    "title": "⏱️ Precision Split Stopwatch & HIIT Interval Timer",
    "description": "Millisecond-accurate lap stopwatch with split deltas, exportable lap times, and customizable HIIT / Tabata workout interval timer with audio alerts.",
    "category": "Productivity & Lifestyle",
    "file": "stopwatch-lap-interval-timer.html",
    "path": "cards/stopwatch-lap-interval-timer.html"
  },
  {
    "id": "stopwatch-timer-title",
    "name": "stopwatch-timer",
    "title": "⏱️ Stopwatch & Lap Timer",
    "description": "Precision stopwatch with lap tracking. Record split times, compare laps, and export your data.",
    "category": "Productivity & Lifestyle",
    "file": "stopwatch-timer.html",
    "path": "cards/stopwatch-timer.html"
  },
  {
    "id": "story-dice-plot-twister-title",
    "name": "story-dice-plot-twister",
    "title": "🎲 Story Dice Plot Twister",
    "description": "Roll story dice for a hero, a setting, a mysterious object and a plot twist — then write the tale. With challenge-mode constraints, story starters and saved prompts for classrooms and young writers.",
    "category": "Writing & Language",
    "file": "story-dice-plot-twister.html",
    "path": "cards/story-dice-plot-twister.html"
  },
  {
    "id": "street-sharing-planner-title",
    "name": "street-sharing-planner",
    "title": "🏘️ Street Sharing Planner",
    "description": "Neighbourly sharing usually fails for two unglamorous reasons: nobody wants to be the one who knocks on a door first, and nobody knows who has what. This builds the sheet and writes the awkward mes...",
    "category": "Wellbeing & Community",
    "file": "street-sharing-planner.html",
    "path": "cards/street-sharing-planner.html"
  },
  {
    "id": "stripe-paypal-fee-calculator-title",
    "name": "stripe-paypal-fee-calculator",
    "title": "💳 Stripe & PayPal Fee Calculator",
    "description": "Reverse a published percentage + pence fee so you know what you keep, or what to charge to net a target. Default rates are the common UK consumer-card / PayPal numbers — your contract may differ.",
    "category": "Finance & Money",
    "file": "stripe-paypal-fee-calculator.html",
    "path": "cards/stripe-paypal-fee-calculator.html"
  },
  {
    "id": "structural-beam-stress-title",
    "name": "structural-beam-stress",
    "title": "🏗️ The Stress Gallery",
    "description": "Apply loads to a beam and watch stress propagate in real time. See shear force and bending moment diagrams update live. The colour map shows where failure begins — red zones are where your shelf, j...",
    "category": "Museum & Collection",
    "file": "structural-beam-stress.html",
    "path": "cards/structural-beam-stress.html"
  },
  {
    "id": "stud-framing-calculator-title",
    "name": "stud-framing-calculator",
    "title": "🧱 Stud & Wall Framing Calculator",
    "description": "Frame a wall the way a carpenter would: enter the wall length, stud spacing, openings and corners, and get the stud count, plate lumber and headers to order.",
    "category": "Home & DIY",
    "file": "stud-framing-calculator.html",
    "path": "cards/stud-framing-calculator.html"
  },
  {
    "id": "studentloan-title",
    "name": "studentloan",
    "title": "💰 Student Loan Calculator",
    "description": "Calculate student loan payments, total interest, and repayment timeline. Compare different repayment plans and see how extra payments can save you money. This site is supported by user contributions .",
    "category": "Finance & Money",
    "file": "studentloan.html",
    "path": "cards/studentloan.html"
  },
  {
    "id": "studyplanner-title",
    "name": "studyplanner",
    "title": "📚 Study Planner",
    "description": "Plan your study sessions, track progress, and stay focused with a built-in Pomodoro timer. All data saved locally in your browser.",
    "category": "Productivity & Lifestyle",
    "file": "studyplanner.html",
    "path": "cards/studyplanner.html"
  },
  {
    "id": "subnet-cidr-network-calculator-title",
    "name": "subnet-cidr-network-calculator",
    "title": "🌐 Subnet & CIDR Calculator",
    "description": "Calculate IPv4 subnets, network boundaries, usable host ranges, and binary bit allocation. Essential for cloud VPCs, DevOps, and network routing.",
    "category": "Science & Engineering",
    "file": "subnet-cidr-network-calculator.html",
    "path": "cards/subnet-cidr-network-calculator.html"
  },
  {
    "id": "subscription-title",
    "name": "subscription",
    "title": "Subscription Tracker",
    "description": "Track your subscriptions, manage renewals, and optimize spending",
    "category": "Finance & Money",
    "file": "subscription.html",
    "path": "cards/subscription.html"
  },
  {
    "id": "sudoku-trainer-title",
    "name": "sudoku-trainer",
    "title": "🧩 Sudoku Trainer (unique puzzles, hints & solver)",
    "description": "Play a freshly generated Sudoku with a guaranteed unique solution, get hints, or reveal the solution. Every puzzle is built on your device — nothing is fetched or sent.",
    "category": "MrProphecy Arcade",
    "file": "sudoku-trainer.html",
    "path": "cards/sudoku-trainer.html"
  },
  {
    "id": "summary-generator-title",
    "name": "summary-generator",
    "title": "AI-Style Summary Generator",
    "description": "AI-Style Summary Generator Generate intelligent summaries using advanced text analysis algorithms",
    "category": "Writing & Language",
    "file": "summary-generator.html",
    "path": "cards/summary-generator.html"
  },
  {
    "id": "sundial-designer-gnomonics-title",
    "name": "sundial-designer-gnomonics",
    "title": "🌞 Sundial Designer",
    "description": "A sundial only works at the latitude it was cut for, which is why the garden-centre ones are decorative rather than accurate. Give it your latitude and this lays out the hour lines properly — the a...",
    "category": "Astronomy & Space",
    "file": "sundial-designer-gnomonics.html",
    "path": "cards/sundial-designer-gnomonics.html"
  },
  {
    "id": "sundial-gnomon-angle-title",
    "name": "sundial-gnomon-angle",
    "title": "☀️ The Sundial Bench",
    "description": "A horizontal dial’s gnomon must sit in the plane of the Earth’s axis. Its style angle equals the site’s latitude. Hour-line angles follow tan(H) = sin(φ) · tan(t) where t is the hour angle. The ben...",
    "category": "Astronomy & Space",
    "file": "sundial-gnomon-angle.html",
    "path": "cards/sundial-gnomon-angle.html"
  },
  {
    "id": "sunrise-sunset-calculator-title",
    "name": "sunrise-sunset-calculator",
    "title": "🌅 Sunrise & Sunset Calculator",
    "description": "Compute sunrise, solar noon and sunset from latitude, longitude and date using the NOAA solar-position equations. Runs entirely in the browser — no weather API, no location permission required.",
    "category": "Astronomy & Space",
    "file": "sunrise-sunset-calculator.html",
    "path": "cards/sunrise-sunset-calculator.html"
  },
  {
    "id": "svg-path-optimizer-cleaner-title",
    "name": "svg-path-optimizer-cleaner",
    "title": "⚡ SVG Path Optimizer & Minifier",
    "description": "Minify and clean SVG markup, remove metadata, editor bloat and unused namespaces, round decimal precision, preview live, and copy optimized SVG.",
    "category": "Algorithms & Computer Science",
    "file": "svg-path-optimizer-cleaner.html",
    "path": "cards/svg-path-optimizer-cleaner.html"
  },
  {
    "id": "svg-path-visualizer-editor-title",
    "name": "svg-path-visualizer-editor",
    "title": "📐 SVG Path Visualizer",
    "description": "Inspect, edit, and optimize SVG path data (d=\"...\") in real time. Visualizes anchor nodes, control handles, bounding box, and minified code.",
    "category": "Productivity & Lifestyle",
    "file": "svg-path-visualizer-editor.html",
    "path": "cards/svg-path-visualizer-editor.html"
  },
  {
    "id": "swimming-pace-calculator-title",
    "name": "swimming-pace-calculator",
    "title": "🏊 Swimming Pace & CSS Calculator",
    "description": "Turn a swim time into pace per 100 m, per length and full splits, then — if you have a 200 m and a 400 m test time — get your Critical Swim Speed and the training zones built around it.",
    "category": "Sports",
    "file": "swimming-pace-calculator.html",
    "path": "cards/swimming-pace-calculator.html"
  },
  {
    "id": "syllable-counter-title",
    "name": "syllable-counter",
    "title": "🔤 Syllable Counter",
    "description": "Heuristic English syllable count (vowel groups, silent e, -le, some -ed/-es). Good enough for haiku drafts and readability checks — not a dictionary.",
    "category": "Interactive Art & Living Worlds",
    "file": "syllable-counter.html",
    "path": "cards/syllable-counter.html"
  },
  {
    "id": "synapse-thought-constellation-network-title",
    "name": "synapse-thought-constellation-network",
    "title": "🧠 NeuroSynapse Graph",
    "description": "An organic neural graph where thoughts, insights, and memories connect via pulsating synaptic axons. Fire bio-electric action potentials, watch ideas resonate across clusters, and author collective...",
    "category": "Interactive Art & Living Worlds",
    "file": "synapse-thought-constellation-network.html",
    "path": "cards/synapse-thought-constellation-network.html"
  },
  {
    "id": "synonym-finder-title",
    "name": "synonym-finder",
    "title": "🔄 Synonym Finder",
    "description": "Find better words — synonyms and near-synonyms for 100+ common English words, with usage tips for the tricky ones.",
    "category": "Writing & Language",
    "file": "synonym-finder.html",
    "path": "cards/synonym-finder.html"
  },
  {
    "id": "tabata-interval-timer-title",
    "name": "tabata-interval-timer",
    "title": "🔥 Tabata Timer",
    "description": "Classic Tabata is 8 rounds of 20 s work / 10 s rest (4 minutes). Phone speakers optional. If you prefer reduced motion, the digits still count without the pulse.",
    "category": "Health & Fitness",
    "file": "tabata-interval-timer.html",
    "path": "cards/tabata-interval-timer.html"
  },
  {
    "id": "table-tennis-scorekeeper-title",
    "name": "table-tennis-scorekeeper",
    "title": "🏓 Table Tennis Scorer",
    "description": "Rally scoring to 11, win by two — no cap, so a deuce game can run long. Tap to score and it tracks games and the best-of-five (or seven) match for you.",
    "category": "Sports",
    "file": "table-tennis-scorekeeper.html",
    "path": "cards/table-tennis-scorekeeper.html"
  },
  {
    "id": "tap-drill-size-chart-title",
    "name": "tap-drill-size-chart",
    "title": "🔩 Tap Drill Size",
    "description": "Close-enough tap drill ≈ major diameter − pitch (75% thread). Metric coarse plus a few UNC sizes. For production work use the machinist’s table for your material.",
    "category": "Science & Engineering",
    "file": "tap-drill-size-chart.html",
    "path": "cards/tap-drill-size-chart.html"
  },
  {
    "id": "targetheartrate-title",
    "name": "targetheartrate",
    "title": "❤️ Target Heart Rate Calculator",
    "description": "Calculate your optimal heart rate zones for effective exercise training. Based on American Heart Association guidelines.",
    "category": "Health & Fitness",
    "file": "targetheartrate.html",
    "path": "cards/targetheartrate.html"
  },
  {
    "id": "taskprioritizer-title",
    "name": "taskprioritizer",
    "title": "📋 Task Prioritizer Matrix",
    "description": "Use the Eisenhower Matrix to prioritize tasks by urgency and importance. Based on the time management framework.",
    "category": "Productivity & Lifestyle",
    "file": "taskprioritizer.html",
    "path": "cards/taskprioritizer.html"
  },
  {
    "id": "tax-title",
    "name": "tax",
    "title": "💰 Tax Estimator & Calculator",
    "description": "Estimate income tax, national insurance, and take-home pay for UK taxpayers. Based on 2024-25 UK tax bands.",
    "category": "Finance & Money",
    "file": "tax.html",
    "path": "cards/tax.html"
  },
  {
    "id": "tdee-title",
    "name": "tdee",
    "title": "⚡ TDEE & Calorie Calculator",
    "description": "Calculate your Total Daily Energy Expenditure (TDEE) and calorie needs for weight goals. Based on Mifflin-St Jeor equation.",
    "category": "Health & Fitness",
    "file": "tdee.html",
    "path": "cards/tdee.html"
  },
  {
    "id": "tectonic-plate-drift-calculator-title",
    "name": "tectonic-plate-drift-calculator",
    "title": "🌋 Tectonic Plate Drift Calculator",
    "description": "The ground under you is moving right now. Pick a place and its tectonic plate and this rotates it about the plate's Euler pole — the real way plate motion is described — to give the present-day spe...",
    "category": "Science & Engineering",
    "file": "tectonic-plate-drift-calculator.html",
    "path": "cards/tectonic-plate-drift-calculator.html"
  },
  {
    "id": "telescope-collimation-check-title",
    "name": "telescope-collimation-check",
    "title": "🔭 Telescope Collimation Check",
    "description": "How precisely your secondary and primary need to be aligned for the images you want, and what a star test tells you about the error you actually have. Based on the wavefront tolerance criteria from...",
    "category": "Astronomy & Space",
    "file": "telescope-collimation-check.html",
    "path": "cards/telescope-collimation-check.html"
  },
  {
    "id": "telescope-eyepiece-calculator-title",
    "name": "telescope-eyepiece-calculator",
    "title": "🔭 Eyepiece & Magnification Calculator",
    "description": "Work out what an eyepiece actually gives you on a given telescope: magnification, exit pupil, true field of view and the practical limits. Covers Barlows and finds your maximum useful power.",
    "category": "Astronomy & Space",
    "file": "telescope-eyepiece-calculator.html",
    "path": "cards/telescope-eyepiece-calculator.html"
  },
  {
    "id": "telescope-limiting-resolver-title",
    "name": "telescope-limiting-resolver",
    "title": "🌟 Resolution & Limiting Magnitude",
    "description": "What can your aperture actually split, and how faint can it go? Computes the Dawes and Rayleigh limits, the theoretical limiting magnitude, and the doubles and deep-sky targets that fall within reach.",
    "category": "Astronomy & Space",
    "file": "telescope-limiting-resolver.html",
    "path": "cards/telescope-limiting-resolver.html"
  },
  {
    "id": "tempo-map-title",
    "name": "tempo-map",
    "title": "🎵 Tempo & BPM Map",
    "description": "Create tempo maps for musical compositions with BPM calculations and time conversions. Educational tool for musicians and composers.",
    "category": "Music & Audio",
    "file": "tempo-map.html",
    "path": "cards/tempo-map.html"
  },
  {
    "id": "tenancy-deposit-calculator-title",
    "name": "tenancy-deposit-calculator",
    "title": "🏠 Tenancy Deposit Calculator (England)",
    "description": "Check your deposit against the statutory cap, see when it must be protected and returned, and understand the remedies if the landlord gets it wrong. England rules; ask for full compliance history b...",
    "category": "Finance & Money",
    "file": "tenancy-deposit-calculator.html",
    "path": "cards/tenancy-deposit-calculator.html"
  },
  {
    "id": "tennis-live-scorer-title",
    "name": "tennis-live-scorer",
    "title": "🎾 Tennis Match Scorer",
    "description": "Score a match point by point with the correct rules handled for you: deuce and advantage, sets to six with a two-game lead, a seven-point tiebreak at six-all, and best-of-three or best-of-five matc...",
    "category": "Sports",
    "file": "tennis-live-scorer.html",
    "path": "cards/tennis-live-scorer.html"
  },
  {
    "id": "text-binary-converter-title",
    "name": "text-binary-converter",
    "title": "🔢 Text ↔ Binary Converter",
    "description": "Convert text to binary and back. Supports ASCII, UTF-8, and custom bit lengths. Perfect for learning computer science.",
    "category": "Algorithms & Computer Science",
    "file": "text-binary-converter.html",
    "path": "cards/text-binary-converter.html"
  },
  {
    "id": "text-case-converter-toolkit-title",
    "name": "text-case-converter-toolkit",
    "title": "🔠 Text Case Converter Toolkit",
    "description": "Instantly convert text between UPPERCASE, lowercase, Title Case, Sentence case, camelCase, PascalCase, snake_case, kebab-case, CONSTANT_CASE, dot.case, aLtErNaTiNg and reversed. One click to copy. ...",
    "category": "Algorithms & Computer Science",
    "file": "text-case-converter-toolkit.html",
    "path": "cards/text-case-converter-toolkit.html"
  },
  {
    "id": "text-case-converter-title",
    "name": "text-case-converter",
    "title": "🔡 Text Case Converter",
    "description": "Paste anything and get it back in every case at once: UPPER, lower, Title Case, Sentence case, camelCase, PascalCase, snake_case, kebab-case, CONSTANT_CASE, dot.case, aLtErNaTiNg and reversed. Clic...",
    "category": "Algorithms & Computer Science",
    "file": "text-case-converter.html",
    "path": "cards/text-case-converter.html"
  },
  {
    "id": "text-case-slug-converter-title",
    "name": "text-case-slug-converter",
    "title": "🔠 Text Case & Slug Converter",
    "description": "Convert a headline, phrase or identifier into title case, sentence case, camelCase, snake_case, kebab-case and a URL-friendly slug at once. Handy for copy edits, filenames, database fields and clea...",
    "category": "SaaS & Business Killers",
    "file": "text-case-slug-converter.html",
    "path": "cards/text-case-slug-converter.html"
  },
  {
    "id": "text-diff-checker-title",
    "name": "text-diff-checker",
    "title": "🔎 Text Diff Checker",
    "description": "Compare two versions of text and see additions, removals and unchanged passages in a clean unified diff. Choose line-by-line for documents and code, or word-by-word for short edits. Everything is c...",
    "category": "SaaS & Business Killers",
    "file": "text-diff-checker.html",
    "path": "cards/text-diff-checker.html"
  },
  {
    "id": "text-diff-compare-checker-title",
    "name": "text-diff-compare-checker",
    "title": "🔍 Text Diff & Compare Checker",
    "description": "Paste two versions of any text and see exactly what changed — line by line or word by word — with additions and deletions highlighted. Runs entirely in your browser; nothing is uploaded.",
    "category": "Algorithms & Computer Science",
    "file": "text-diff-compare-checker.html",
    "path": "cards/text-diff-compare-checker.html"
  },
  {
    "id": "text-diff-viewer-title",
    "name": "text-diff-viewer",
    "title": "📝 Text Diff Viewer",
    "description": "Compare two texts side by side and see exactly what changed. Added, removed, and modified lines highlighted.",
    "category": "Algorithms & Computer Science",
    "file": "text-diff-viewer.html",
    "path": "cards/text-diff-viewer.html"
  },
  {
    "id": "text-statistics-title",
    "name": "text-statistics",
    "title": "📊 Text Statistics Analyzer",
    "description": "Comprehensive text analysis: word count, character count, sentence count, reading time, readability score, and more.",
    "category": "Mathematics",
    "file": "text-statistics.html",
    "path": "cards/text-statistics.html"
  },
  {
    "id": "text-to-ascii-art-title",
    "name": "text-to-ascii-art",
    "title": "🎨 Text to ASCII Art",
    "description": "Convert text into ASCII art using various fonts. Perfect for terminal banners, README files, and fun messages.",
    "category": "Productivity & Lifestyle",
    "file": "text-to-ascii-art.html",
    "path": "cards/text-to-ascii-art.html"
  },
  {
    "id": "text-to-handwriting-title",
    "name": "text-to-handwriting",
    "title": "✍️ Text to Handwriting",
    "description": "Convert typed text into realistic handwriting. Choose styles, sizes, and colors. Download as image.",
    "category": "Writing & Language",
    "file": "text-to-handwriting.html",
    "path": "cards/text-to-handwriting.html"
  },
  {
    "id": "text-to-image-title",
    "name": "text-to-image",
    "title": "🖼️ Text to Image Generator",
    "description": "Create images from text. Choose fonts, colors, backgrounds, and sizes. Perfect for social media posts and headers.",
    "category": "Writing & Language",
    "file": "text-to-image.html",
    "path": "cards/text-to-image.html"
  },
  {
    "id": "text-to-speech-reader-voices-title",
    "name": "text-to-speech-reader-voices",
    "title": "🔊 Text-to-Speech Reader (Offline Browser Voices)",
    "description": "Paste any text and have your device read it aloud using the voices already built into your browser or operating system — no upload, no account. Choose voice and language, adjust speed and pitch, fo...",
    "category": "Writing & Language",
    "file": "text-to-speech-reader-voices.html",
    "path": "cards/text-to-speech-reader-voices.html"
  },
  {
    "id": "text-to-speech-title",
    "name": "text-to-speech",
    "title": "🔊 Text to Speech",
    "description": "Convert text to speech using your browser's built-in voice synthesis. Choose voices, adjust speed and pitch.",
    "category": "Writing & Language",
    "file": "text-to-speech.html",
    "path": "cards/text-to-speech.html"
  },
  {
    "id": "therapy-body-scan-dialogue-title",
    "name": "therapy-body-scan-dialogue",
    "title": "🗣️ Talk to Your Body (It's Been Trying to Tell You Something)",
    "description": "Your body stores emotions your mind has suppressed. Tension, pain, fatigue — these aren't random. They're messages. This guided dialogue helps you listen to what your body has been holding.",
    "category": "Wellbeing & Community",
    "file": "therapy-body-scan-dialogue.html",
    "path": "cards/therapy-body-scan-dialogue.html"
  },
  {
    "id": "therapy-emotional-inheritance-title",
    "name": "therapy-emotional-inheritance",
    "title": "🧬 The Emotions You Inherited (But Never Chose)",
    "description": "Some of your deepest patterns — guilt, anxiety, people-pleasing, scarcity fear — aren't yours. They were passed down through your family like heirlooms you never asked for. This tool helps you iden...",
    "category": "Wellbeing & Community",
    "file": "therapy-emotional-inheritance.html",
    "path": "cards/therapy-emotional-inheritance.html"
  },
  {
    "id": "therapy-grief-of-invisible-losses-title",
    "name": "therapy-grief-of-invisible-losses",
    "title": "🕯️ The Grief No One Validates",
    "description": "You've been carrying losses that don't have funerals — the friendship that faded, the version of yourself you thought you'd be, the childhood you deserved but didn't get. This tool validates the gr...",
    "category": "Wellbeing & Community",
    "file": "therapy-grief-of-invisible-losses.html",
    "path": "cards/therapy-grief-of-invisible-losses.html"
  },
  {
    "id": "therapy-identity-shedding-title",
    "name": "therapy-identity-shedding",
    "title": "🐍 The Identities You're Dragging Behind You",
    "description": "You're carrying identities that expired years ago — \"the shy one,\" \"the responsible one,\" \"the one who doesn't need help.\" They were useful once. Now they're cages. This tool helps you see which on...",
    "category": "Wellbeing & Community",
    "file": "therapy-identity-shedding.html",
    "path": "cards/therapy-identity-shedding.html"
  },
  {
    "id": "therapy-inner-critic-reframe-title",
    "name": "therapy-inner-critic-reframe",
    "title": "🛡️ Your Inner Critic Is Trying to Save You",
    "description": "Your inner critic isn't your enemy — it's a terrified protector stuck in the past. Meet it, understand what it's protecting you from, and gently update its threat model.",
    "category": "Wellbeing & Community",
    "file": "therapy-inner-critic-reframe.html",
    "path": "cards/therapy-inner-critic-reframe.html"
  },
  {
    "id": "therapy-micro-acts-of-defiance-title",
    "name": "therapy-micro-acts-of-defiance",
    "title": "✊ Tiny Revolts Against Your Own Prison",
    "description": "You don't need a life overhaul. You need a micro-act of defiance against the rules you've been following that were never yours. One small, deliberate act of \"I'm allowed\" can crack open years of se...",
    "category": "Wellbeing & Community",
    "file": "therapy-micro-acts-of-defiance.html",
    "path": "cards/therapy-micro-acts-of-defiance.html"
  },
  {
    "id": "therapy-past-self-gratitude-title",
    "name": "therapy-past-self-gratitude",
    "title": "📖 You're Already Living Your Dream (You Just Forgot)",
    "description": "Five years ago, you wished for what you have now. This tool reconnects you with the gap between longing and having — the most overlooked source of gratitude that exists.",
    "category": "Wellbeing & Community",
    "file": "therapy-past-self-gratitude.html",
    "path": "cards/therapy-past-self-gratitude.html"
  },
  {
    "id": "therapy-third-person-narrator-title",
    "name": "therapy-third-person-narrator",
    "title": "📖 See Your Life Through a Narrator's Eyes",
    "description": "When you're inside your own story, everything feels overwhelming. This tool reframes your situation as a chapter in a novel — creating the psychological distance that turns suffering into narrative...",
    "category": "Wellbeing & Community",
    "file": "therapy-third-person-narrator.html",
    "path": "cards/therapy-third-person-narrator.html"
  },
  {
    "id": "therapy-uncertainty-tolerance-title",
    "name": "therapy-uncertainty-tolerance",
    "title": "🌊 Learning to Swim in Not Knowing",
    "description": "Most of your suffering comes not from bad outcomes, but from the gap between \"I need to know\" and \"I can't know yet.\" This tool trains your tolerance for uncertainty — the single most underrated me...",
    "category": "Wellbeing & Community",
    "file": "therapy-uncertainty-tolerance.html",
    "path": "cards/therapy-uncertainty-tolerance.html"
  },
  {
    "id": "therapy-values-time-gap-title",
    "name": "therapy-values-time-gap",
    "title": "⏰ Your Life Is Telling a Different Story Than You Think",
    "description": "You say you value family, health, creativity. But where does your time actually go? This tool reveals the gap between your stated values and your lived values — the most honest mirror there is.",
    "category": "Wellbeing & Community",
    "file": "therapy-values-time-gap.html",
    "path": "cards/therapy-values-time-gap.html"
  },
  {
    "id": "therapy-worry-sorter-title",
    "name": "therapy-worry-sorter",
    "title": "🧠 The Worry Sorter: Actionable vs. Noise",
    "description": "Your brain treats all worries as equally urgent. They're not. This tool forces you to sort your worries into \"I can act on this\" and \"I'm just spinning\" — then creates a concrete plan for the first...",
    "category": "Wellbeing & Community",
    "file": "therapy-worry-sorter.html",
    "path": "cards/therapy-worry-sorter.html"
  },
  {
    "id": "thermal-wall-simulator-title",
    "name": "thermal-wall-simulator",
    "title": "🧱 The Thermal Wall",
    "description": "Watch heat flow through building materials in real time. A thermal wave propagates from a warm room through brick, insulation, glass or wood — Fourier's law made visible. See why a 100mm air gap is...",
    "category": "Museum & Collection",
    "file": "thermal-wall-simulator.html",
    "path": "cards/thermal-wall-simulator.html"
  },
  {
    "id": "thermodynamics-title",
    "name": "thermodynamics",
    "title": "🔥 Thermodynamics Calculator",
    "description": "Calculate heat transfer, efficiency, entropy, and explore thermodynamics principles. Essential tool for physics, engineering, and chemistry.",
    "category": "Science & Engineering",
    "file": "thermodynamics.html",
    "path": "cards/thermodynamics.html"
  },
  {
    "id": "thing-namer-generator-title",
    "name": "thing-namer-generator",
    "title": "🏷️ The Thing Namer",
    "description": "Naming things is one of the two hard problems in computer science (along with cache invalidation and off-by-one errors). Point it at a thing and it will name it — band, pet, D&D character, startup,...",
    "category": "Productivity & Lifestyle",
    "file": "thing-namer-generator.html",
    "path": "cards/thing-namer-generator.html"
  },
  {
    "id": "thumbnail-generator-title",
    "name": "thumbnail-generator",
    "title": "🖼️ Universal Thumbnail Generator",
    "description": "Generate perfectly sized thumbnails for any platform with advanced editing tools. No upload required - all processing happens locally.",
    "category": "Productivity & Lifestyle",
    "file": "thumbnail-generator.html",
    "path": "cards/thumbnail-generator.html"
  },
  {
    "id": "tic-tac-toe-title",
    "name": "tic-tac-toe",
    "title": "🎮 Tic Tac Toe Game",
    "description": "Play Tic Tac Toe against the computer or a friend. Features three difficulty levels and game statistics. Classic strategy game reimagined.",
    "category": "Productivity & Lifestyle",
    "file": "tic-tac-toe.html",
    "path": "cards/tic-tac-toe.html"
  },
  {
    "id": "tidal-window-crossing-planner-title",
    "name": "tidal-window-crossing-planner",
    "title": "🌊 Tidal Window & Crossing Planner",
    "description": "Two kinds of people watch the tide: sailors who need enough water under the keel, and everyone crossing a causeway, ford or sandbar who needs the water gone. Give it one high water and one low wate...",
    "category": "Science & Engineering",
    "file": "tidal-window-crossing-planner.html",
    "path": "cards/tidal-window-crossing-planner.html"
  },
  {
    "id": "tile-flooring-estimator-title",
    "name": "tile-flooring-estimator",
    "title": "🧱 Tile & Flooring Estimator",
    "description": "Calculate tiles, planks, or carpet needed for any room — including waste and cuts.",
    "category": "Home & DIY",
    "file": "tile-flooring-estimator.html",
    "path": "cards/tile-flooring-estimator.html"
  },
  {
    "id": "timelapse-interval-calculator-title",
    "name": "timelapse-interval-calculator",
    "title": "⏱️ Timelapse Interval",
    "description": "Shots needed = clip length × frame rate. Real time covered = shots × interval. Leave the battery and a bigger card than you think. Sunset clouds often want 2–5 s; construction days want 30–60 s.",
    "category": "Productivity & Lifestyle",
    "file": "timelapse-interval-calculator.html",
    "path": "cards/timelapse-interval-calculator.html"
  },
  {
    "id": "timer-title",
    "name": "timer",
    "title": "⏱️ Advanced Timer & Stopwatch",
    "description": "Advanced timer with countdown, stopwatch, intervals, lap times, and multiple alarms. Perfect for workouts, cooking, study sessions, and productivity.",
    "category": "Productivity & Lifestyle",
    "file": "timer.html",
    "path": "cards/timer.html"
  },
  {
    "id": "times-tables-drill-trainer-title",
    "name": "times-tables-drill-trainer",
    "title": "🔢 Times Tables Drill Trainer",
    "description": "Drill the 1–12 times tables with instant feedback, streak tracking and a review of the facts you get wrong. Includes a full 12×12 grid and memory tricks. Everything runs in your browser — no sign-u...",
    "category": "Mathematics",
    "file": "times-tables-drill-trainer.html",
    "path": "cards/times-tables-drill-trainer.html"
  },
  {
    "id": "timezone-title",
    "name": "timezone",
    "title": "🌍 Time Zone Converter",
    "description": "Convert any date and time between time zones. Supports all major world time zones.",
    "category": "Productivity & Lifestyle",
    "file": "timezone.html",
    "path": "cards/timezone.html"
  },
  {
    "id": "tip-calculator-title",
    "name": "tip-calculator",
    "title": "🧾 Tip Calculator",
    "description": "Split a bill and tip fairly — choose a percentage or a custom tip, share between friends, and see per-person totals.",
    "category": "Finance & Money",
    "file": "tip-calculator.html",
    "path": "cards/tip-calculator.html"
  },
  {
    "id": "tip-split-bill-per-person-title",
    "name": "tip-split-bill-per-person",
    "title": "🍽️ Restaurant Bill Splitter with Itemised Shares",
    "description": "Split a restaurant bill fairly: add each dish and tick who shared it, set a service charge or tip, and get an exact per-person total including their proportional share of tax and tip. Handles \"I on...",
    "category": "Finance & Money",
    "file": "tip-split-bill-per-person.html",
    "path": "cards/tip-split-bill-per-person.html"
  },
  {
    "id": "tipcalculator-title",
    "name": "tipcalculator",
    "title": "💸 Tip & Split Calculator",
    "description": "Calculate tips, split bills, and see exactly how much everyone owes. Supports multiple currencies!",
    "category": "Productivity & Lifestyle",
    "file": "tipcalculator.html",
    "path": "cards/tipcalculator.html"
  },
  {
    "id": "tire-size-comparison-calculator-title",
    "name": "tire-size-comparison-calculator",
    "title": "🛞 Tyre Size Comparison",
    "description": "Compare two metric tyre sizes (e.g. 225/45R17 vs 235/40R18): overall diameter, circumference, sidewall and the speedometer error if you swap them. Not a load or speed-rating check.",
    "category": "Productivity & Lifestyle",
    "file": "tire-size-comparison-calculator.html",
    "path": "cards/tire-size-comparison-calculator.html"
  },
  {
    "id": "tongue-twister-trainer-title",
    "name": "tongue-twister-trainer",
    "title": "🎤 Tongue Twister Trainer",
    "description": "Practise classic tongue twisters at your own pace, then beat the clock: read as many as you can in 30 seconds.",
    "category": "Writing & Language",
    "file": "tongue-twister-trainer.html",
    "path": "cards/tongue-twister-trainer.html"
  },
  {
    "id": "tornado-fujita-lab-title",
    "name": "tornado-fujita-lab",
    "title": "🌪️ Tornado & EF-Scale Lab",
    "description": "Build a supercell in real time. CAPE (buoyant energy), 0–6 km wind shear, core radius and surface roughness control rotation, funnel formation, damage and the Enhanced Fujita rating — with the live...",
    "category": "Interactive Art & Living Worlds",
    "file": "tornado-fujita-lab.html",
    "path": "cards/tornado-fujita-lab.html"
  },
  {
    "id": "torsional-vibration-critical-speed-title",
    "name": "torsional-vibration-critical-speed",
    "title": "⚡ Torsional Vibration Lab",
    "description": "Calculate torsional stiffness ($k_t = \\frac{GJ}{L}$), natural angular frequencies ($\\omega_n = \\sqrt{k_t/I}$), and critical whirling RPM. Analyze engine harmonic orders ($1\\times, 2\\times, 3\\times,...",
    "category": "Science & Engineering",
    "file": "torsional-vibration-critical-speed.html",
    "path": "cards/torsional-vibration-critical-speed.html"
  },
  {
    "id": "tournament-bracket-generator-title",
    "name": "tournament-bracket-generator",
    "title": "🏆 Tournament Bracket Generator",
    "description": "Knock out a single-elimination draw in seconds. Pick how many teams, name them if you like, and get a seeded bracket with the right number of byes, in a form you can read or copy out.",
    "category": "Sports",
    "file": "tournament-bracket-generator.html",
    "path": "cards/tournament-bracket-generator.html"
  },
  {
    "id": "towers-of-hanoi-title",
    "name": "towers-of-hanoi",
    "title": "🗼 Towers of Hanoi",
    "description": "Move the stack from peg A to peg C, never putting a bigger disk on a smaller one. The catch: the optimal solution is 2ⁿ &minus; 1 moves, so 8 disks means 255 moves — recursion made visible. Solve i...",
    "category": "Algorithms & Computer Science",
    "file": "towers-of-hanoi.html",
    "path": "cards/towers-of-hanoi.html"
  },
  {
    "id": "tr3b-anti-gravity-flight-calculator-title",
    "name": "tr3b-anti-gravity-flight-calculator",
    "title": "🛸 TR-3B Flight Simulator",
    "description": "Simulate the theoretical physics of the triangular TR-3B aerospace platform. Calculates Mercury-based Magnetic Field Disruptor (MFD) plasma acceleration, inertial mass reduction percentage, and sup...",
    "category": "Science & Engineering",
    "file": "tr3b-anti-gravity-flight-calculator.html",
    "path": "cards/tr3b-anti-gravity-flight-calculator.html"
  },
  {
    "id": "transformer-calculator-title",
    "name": "transformer-calculator",
    "title": "⚡ Transformer Sizing Calculator",
    "description": "Estimate transformer size for electrical loads. ⚠️ EDUCATIONAL ONLY — Always verify with a qualified engineer and local standards.",
    "category": "Science & Engineering",
    "file": "transformer-calculator.html",
    "path": "cards/transformer-calculator.html"
  },
  {
    "id": "translation-helper-title",
    "name": "translation-helper",
    "title": "🌍 Translation Helper",
    "description": "Translate text between languages with style and tone analysis. Includes language detection and clarity checking!",
    "category": "Writing & Language",
    "file": "translation-helper.html",
    "path": "cards/translation-helper.html"
  },
  {
    "id": "transposer-title",
    "name": "transposer",
    "title": "🎵 Music Transposer",
    "description": "Transpose chords, melodies, and entire progressions between keys. ⚠️ EDUCATIONAL TOOL — Verify with music teacher or professional resources.",
    "category": "Music & Audio",
    "file": "transposer.html",
    "path": "cards/transposer.html"
  },
  {
    "id": "travel-title",
    "name": "travel",
    "title": "✈️ Travel Trip Planner",
    "description": "Plan your perfect trip with detailed itineraries, budget tracking, and smart recommendations. Get personalized suggestions based on your preferences!",
    "category": "Productivity & Lifestyle",
    "file": "travel.html",
    "path": "cards/travel.html"
  },
  {
    "id": "triathlon-race-planner-title",
    "name": "triathlon-race-planner",
    "title": "🏊‍♂️ Triathlon Race Planner",
    "description": "Build a race-day plan: pick a distance, enter your swim pace, bike speed, run pace and transitions, and this gives you the time for each leg and your finish line.",
    "category": "Sports",
    "file": "triathlon-race-planner.html",
    "path": "cards/triathlon-race-planner.html"
  },
  {
    "id": "trigonometry-title",
    "name": "trigonometry",
    "title": "🎯 Foundation & Unit Circle",
    "description": "Sin = Opposite / Hypotenuse Cos = Adjacent / Hypotenuse Tan = Opposite / Adjacent",
    "category": "Mathematics",
    "file": "trigonometry.html",
    "path": "cards/trigonometry.html"
  },
  {
    "id": "true-scale-of-space-3d-title",
    "name": "true-scale-of-space-3d",
    "title": "🌀 True Scale of Space",
    "description": "Every body is drawn at its real size and real distance — no compression. Start at the Earth–Moon system (the Moon's orbit is 60 Earth radii across!) and zoom out through the inner planets, the gian...",
    "category": "Astronomy & Space",
    "file": "true-scale-of-space-3d.html",
    "path": "cards/true-scale-of-space-3d.html"
  },
  {
    "id": "truth-table-generator-title",
    "name": "truth-table-generator",
    "title": "🧮 Truth Table Generator",
    "description": "Generate truth tables for logical expressions. Supports AND, OR, NOT, XOR, IMPLIES, and IFF operators.",
    "category": "Algorithms & Computer Science",
    "file": "truth-table-generator.html",
    "path": "cards/truth-table-generator.html"
  },
  {
    "id": "tsunami-runup-simulator-title",
    "name": "tsunami-runup-simulator",
    "title": "🌊 Tsunami Runup Simulator",
    "description": "A real 1D shallow-water wave solver (c = √gh, leapfrog scheme) running a subduction-zone tsunami from seafloor rupture to the coast. Watch the wave slow, shoal and amplify — Green's law emerges nat...",
    "category": "Interactive Art & Living Worlds",
    "file": "tsunami-runup-simulator.html",
    "path": "cards/tsunami-runup-simulator.html"
  },
  {
    "id": "tuner-title",
    "name": "tuner",
    "title": "🎸 Instrument Tuner Reference",
    "description": "Reference notes for tuning your instrument. Educational only — verify with your ear or a professional tuner.",
    "category": "Music & Audio",
    "file": "tuner.html",
    "path": "cards/tuner.html"
  },
  {
    "id": "turkey-thaw-cook-time-title",
    "name": "turkey-thaw-cook-time",
    "title": "🦃 Turkey Thaw & Cook Time",
    "description": "Fridge thaw ~24 h per 2–2.5 kg (FSA: 24 h per 2 kg is a safe extra). Oven times are a starting point — always probe 75 °C in the thickest thigh and stuffing. Not a substitute for the label on your ...",
    "category": "Culinary & Food Science",
    "file": "turkey-thaw-cook-time.html",
    "path": "cards/turkey-thaw-cook-time.html"
  },
  {
    "id": "tv-viewing-distance-calculator-title",
    "name": "tv-viewing-distance-calculator",
    "title": "📺 TV Viewing Distance Calculator",
    "description": "Recommend a sofa distance from screen diagonal and resolution. Uses SMPTE 30° field-of-view, THX 40°, and a sharpness seat where 4K/1080p pixels sit at about 1 arc-minute. Advice, not a living-room...",
    "category": "Home & DIY",
    "file": "tv-viewing-distance-calculator.html",
    "path": "cards/tv-viewing-distance-calculator.html"
  },
  {
    "id": "typing-speed-test-title",
    "name": "typing-speed-test",
    "title": "⌨️ Typing Speed Test",
    "description": "Measure your typing speed and accuracy with live feedback. Type the passage, watch your WPM build as you go, and see exactly which characters you missed. Your keystrokes never leave this page.",
    "category": "Writing & Language",
    "file": "typing-speed-test.html",
    "path": "cards/typing-speed-test.html"
  },
  {
    "id": "typing-story-sprint-title",
    "name": "typing-story-sprint",
    "title": "⌨️ Typing Story Sprint",
    "description": "Build typing speed by retyping fascinating true mini-stories — bees, pyramids, photosynthesis. Live WPM, accuracy, tricky-key analysis and personal bests.",
    "category": "Writing & Language",
    "file": "typing-story-sprint.html",
    "path": "cards/typing-story-sprint.html"
  },
  {
    "id": "ucas-tariff-points-calculator-title",
    "name": "ucas-tariff-points-calculator",
    "title": "🎓 UCAS Tariff Points",
    "description": "Add A-level, AS and T Level grades to a running UCAS tariff total. Offers are often “BBB (120)” — this is the current A-level band (A* = 56). Always check the course page; some universities ignore ...",
    "category": "Finance & Money",
    "file": "ucas-tariff-points-calculator.html",
    "path": "cards/ucas-tariff-points-calculator.html"
  },
  {
    "id": "uk-alcohol-units-calculator-title",
    "name": "uk-alcohol-units-calculator",
    "title": "🍺 UK Alcohol Units Calculator",
    "description": "UK units = ABV (%) × volume (ml) ÷ 1,000. The NHS low-risk guideline is 14 units a week, spread out, with several drink-free days. This is arithmetic, not medical advice.",
    "category": "Health & Fitness",
    "file": "uk-alcohol-units-calculator.html",
    "path": "cards/uk-alcohol-units-calculator.html"
  },
  {
    "id": "uk-counties-quiz-title",
    "name": "uk-counties-quiz",
    "title": "🗺️ UK Counties & Regions Quiz",
    "description": "Learn the 48 English counties plus Scotland, Wales and Northern Ireland — match counties to regions in ten-question rounds. Runs entirely in your browser.",
    "category": "MrProphecy Arcade",
    "file": "uk-counties-quiz.html",
    "path": "cards/uk-counties-quiz.html"
  },
  {
    "id": "uk-hallmark-decoder-title",
    "name": "uk-hallmark-decoder",
    "title": "🥈 The Hallmark Bench",
    "description": "British silver and gold are punched with a standard, a town, a maker, and (historically) a date letter. The bench identifies the town mark and the millesimal fineness. Date letters cycle by assay o...",
    "category": "Museum & Collection",
    "file": "uk-hallmark-decoder.html",
    "path": "cards/uk-hallmark-decoder.html"
  },
  {
    "id": "uk-holiday-entitlement-calculator-title",
    "name": "uk-holiday-entitlement-calculator",
    "title": "🏖️ UK Holiday Entitlement",
    "description": "Statutory paid holiday in Great Britain is 5.6 weeks a year (28 days for a 5-day week), which may include bank holidays if your contract says so. Pro-rata for part-time and joiners. Not legal advic...",
    "category": "Finance & Money",
    "file": "uk-holiday-entitlement-calculator.html",
    "path": "cards/uk-holiday-entitlement-calculator.html"
  },
  {
    "id": "uk-postcode-formatter-title",
    "name": "uk-postcode-formatter",
    "title": "📮 UK Postcode Formatter",
    "description": "Uppercase, insert the inward-code space, and check the Royal Mail pattern (e.g. LU1 2AB, EC1A 1BB, W1A 0AX). This is a format check only — it does not look up addresses.",
    "category": "Productivity & Lifestyle",
    "file": "uk-postcode-formatter.html",
    "path": "cards/uk-postcode-formatter.html"
  },
  {
    "id": "underwater-acoustics-sound-speed-title",
    "name": "underwater-acoustics-sound-speed",
    "title": "🐬 Underwater Acoustics Lab",
    "description": "Investigate acoustic wave mechanics in water. Calculate high-precision sound velocity ($c \\approx 1,482\\text{ m/s}$, 4.3× faster than air), bulk modulus incompressibility ($K_s = \\rho c^2 \\approx 2...",
    "category": "Science & Engineering",
    "file": "underwater-acoustics-sound-speed.html",
    "path": "cards/underwater-acoustics-sound-speed.html"
  },
  {
    "id": "unicode-converter-title",
    "name": "unicode-converter",
    "title": "🌐 Unicode Converter",
    "description": "Convert text to Unicode code points, HTML entities, and escape sequences. Supports all Unicode characters.",
    "category": "Algorithms & Computer Science",
    "file": "unicode-converter.html",
    "path": "cards/unicode-converter.html"
  },
  {
    "id": "unit-converter-science-title",
    "name": "unit-converter-science",
    "title": "⚛️ Science Unit Converter",
    "description": "Convert between scientific units — energy, temperature, length, mass, and pressure.",
    "category": "Science & Engineering",
    "file": "unit-converter-science.html",
    "path": "cards/unit-converter-science.html"
  },
  {
    "id": "unit-converter-title",
    "name": "unit-converter",
    "title": "🔬 Scientific Unit Converter",
    "description": "Convert between common scientific units — length, mass, temperature, and energy.",
    "category": "Science & Engineering",
    "file": "unit-converter.html",
    "path": "cards/unit-converter.html"
  },
  {
    "id": "unit-price-comparator-title",
    "name": "unit-price-comparator",
    "title": "🛒 Unit Price Comparator",
    "description": "Shops price things so you cannot compare them: 340 g here, 12 &times; 30 g there, \"3 for £5\" on the shelf edge. Put in what is actually on the shelf and this reduces everything to one number. Handl...",
    "category": "Finance & Money",
    "file": "unit-price-comparator.html",
    "path": "cards/unit-price-comparator.html"
  },
  {
    "id": "unitconverter-title",
    "name": "unitconverter",
    "title": "📏 Everyday Unit Converter",
    "description": "Convert between common units of length, weight, and temperature.",
    "category": "Science & Engineering",
    "file": "unitconverter.html",
    "path": "cards/unitconverter.html"
  },
  {
    "id": "universal-thumbnail-maker-title",
    "name": "universal-thumbnail-maker",
    "title": "🖼️ Thumbnail Preview Tool",
    "description": "Upload an image and preview it as a 16:9 thumbnail. Adjust brightness, contrast, and add overlay text.",
    "category": "Productivity & Lifestyle",
    "file": "universal-thumbnail-maker.html",
    "path": "cards/universal-thumbnail-maker.html"
  },
  {
    "id": "unix-timestamp-converter-title",
    "name": "unix-timestamp-converter",
    "title": "⏱️ Unix Timestamp Converter",
    "description": "Convert between Unix timestamps and human-readable dates. Live clock, batch conversion, and multiple formats.",
    "category": "Algorithms & Computer Science",
    "file": "unix-timestamp-converter.html",
    "path": "cards/unix-timestamp-converter.html"
  },
  {
    "id": "unix-timestamp-date-converter-title",
    "name": "unix-timestamp-date-converter",
    "title": "🕰️ Unix Timestamp Converter",
    "description": "Convert Unix seconds or milliseconds into local time, UTC and ISO 8601 — or turn a date and time back into a timestamp. The conversion uses your device clock and timezone only; nothing is sent to a...",
    "category": "SaaS & Business Killers",
    "file": "unix-timestamp-date-converter.html",
    "path": "cards/unix-timestamp-date-converter.html"
  },
  {
    "id": "unix-timestamp-epoch-converter-title",
    "name": "unix-timestamp-epoch-converter",
    "title": "⏱️ Unix Timestamp Converter",
    "description": "Convert Unix epoch timestamps (seconds, milliseconds, microseconds or nanoseconds — auto-detected) to human dates and back. Shows UTC, your local time, ISO 8601, relative time and the weekday. A li...",
    "category": "Productivity & Lifestyle",
    "file": "unix-timestamp-epoch-converter.html",
    "path": "cards/unix-timestamp-epoch-converter.html"
  },
  {
    "id": "url-encoder-decoder-parser-title",
    "name": "url-encoder-decoder-parser",
    "title": "🔗 URL Encoder, Decoder & Parser",
    "description": "Percent-encode or decode any text (full encodeURIComponent or URL-safe encodeURI), and break a URL into protocol, host, port, path, hash and an editable table of query parameters. Edit a value and ...",
    "category": "Algorithms & Computer Science",
    "file": "url-encoder-decoder-parser.html",
    "path": "cards/url-encoder-decoder-parser.html"
  },
  {
    "id": "url-encoder-decoder-title",
    "name": "url-encoder-decoder",
    "title": "🔗 URL Encoder / Decoder",
    "description": "Encode text to URL-safe format or decode URL-encoded strings. Handles special characters, Unicode, and query parameters.",
    "category": "Algorithms & Computer Science",
    "file": "url-encoder-decoder.html",
    "path": "cards/url-encoder-decoder.html"
  },
  {
    "id": "url-encoder-query-builder-title",
    "name": "url-encoder-query-builder",
    "title": "🔗 URL Encoder & Query Builder",
    "description": "Encode or decode URL text safely, then inspect, edit and rebuild query parameters without losing special characters. It is useful for sharing links, debugging redirects and preparing search or camp...",
    "category": "SaaS & Business Killers",
    "file": "url-encoder-query-builder.html",
    "path": "cards/url-encoder-query-builder.html"
  },
  {
    "id": "user-agent-browser-fingerprint-analyzer-title",
    "name": "user-agent-browser-fingerprint-analyzer",
    "title": "🕵️ User Agent & Browser Client Inspector",
    "description": "Inspect your browser's user agent string, client hints, screen geometry, GPU WebGL renderer, touch capabilities, color depth, and networking status.",
    "category": "Algorithms & Computer Science",
    "file": "user-agent-browser-fingerprint-analyzer.html",
    "path": "cards/user-agent-browser-fingerprint-analyzer.html"
  },
  {
    "id": "utm-campaign-matrix-builder-title",
    "name": "utm-campaign-matrix-builder",
    "title": "🔗 UTM Campaign URL Builder",
    "description": "Generate standardized Google Analytics 4 (GA4) tracking URLs across multiple marketing channels simultaneously. Enforces lowercase slugification, auto-encodes illegal spaces, and exports batch CSVs...",
    "category": "SaaS & Business Killers",
    "file": "utm-campaign-matrix-builder.html",
    "path": "cards/utm-campaign-matrix-builder.html"
  },
  {
    "id": "uuid-generator-title",
    "name": "uuid-generator",
    "title": "🆔 UUID Generator",
    "description": "Generate universally unique identifiers (UUIDs) v4 and v1. Bulk generate, copy, and download.",
    "category": "Algorithms & Computer Science",
    "file": "uuid-generator.html",
    "path": "cards/uuid-generator.html"
  },
  {
    "id": "uuid-guid-bulk-generator-title",
    "name": "uuid-guid-bulk-generator",
    "title": "🆔 UUID / GUID & Random ID Bulk Generator",
    "description": "Generate one or hundreds of UUID v4s, time-ordered UUID v7s, ULIDs, NanoIDs, short IDs or custom-pattern codes using the browser's cryptographic random source. Choose case, braces and separators, t...",
    "category": "Algorithms & Computer Science",
    "file": "uuid-guid-bulk-generator.html",
    "path": "cards/uuid-guid-bulk-generator.html"
  },
  {
    "id": "uuid-random-id-generator-title",
    "name": "uuid-random-id-generator",
    "title": "🆔 UUID & Random ID Generator",
    "description": "Generate cryptographically random UUID v4, time-ordered UUID v7, ULID, NanoID, short IDs and custom-alphabet tokens in bulk. Uses your browser's crypto.getRandomValues — nothing is generated on a s...",
    "category": "Algorithms & Computer Science",
    "file": "uuid-random-id-generator.html",
    "path": "cards/uuid-random-id-generator.html"
  },
  {
    "id": "uuid-ulid-generator-title",
    "name": "uuid-ulid-generator",
    "title": "🆔 UUID & ULID Generator",
    "description": "Generate UUID v4, time-sortable UUID v7 or ULIDs in batches, then copy or download the results. Random bits come from your browser's cryptographic generator when it is available; no identifiers lea...",
    "category": "SaaS & Business Killers",
    "file": "uuid-ulid-generator.html",
    "path": "cards/uuid-ulid-generator.html"
  },
  {
    "id": "van-de-graaff-electrostatic-generator-title",
    "name": "van-de-graaff-electrostatic-generator",
    "title": "⚡ Van de Graaff Generator",
    "description": "Electrostatic museum exhibit. Rubber belt triboelectric charge transport accumulates up to 400 kV on the metal dome, firing high-voltage atmospheric sparks.",
    "category": "Science & Engineering",
    "file": "van-de-graaff-electrostatic-generator.html",
    "path": "cards/van-de-graaff-electrostatic-generator.html"
  },
  {
    "id": "vat-gst-sales-tax-calculator-title",
    "name": "vat-gst-sales-tax-calculator",
    "title": "💷 VAT / GST / Sales Tax Calculator",
    "description": "Add tax to a net price or extract tax from a gross (inc-VAT) figure. Presets cover UK VAT, common EU GST/VAT rates and US-style sales tax. Arithmetic only — not tax advice.",
    "category": "Finance & Money",
    "file": "vat-gst-sales-tax-calculator.html",
    "path": "cards/vat-gst-sales-tax-calculator.html"
  },
  {
    "id": "vat-sales-tax-calculator-title",
    "name": "vat-sales-tax-calculator",
    "title": "🧾 VAT & Sales Tax Calculator (Add or Remove)",
    "description": "Add VAT to a net price or strip it out of a gross price. Pick a country preset (UK 20%, Ireland 23%, Germany 19%, France 20%, etc.) or type any rate. Shows the tax amount, both prices and a quick r...",
    "category": "Finance & Money",
    "file": "vat-sales-tax-calculator.html",
    "path": "cards/vat-sales-tax-calculator.html"
  },
  {
    "id": "vcard-contact-generator-title",
    "name": "vcard-contact-generator",
    "title": "🪪 vCard Generator",
    "description": "Build a vCard 3.0 you can save as .vcf and open on a phone. Stays in the browser — no address book is uploaded.",
    "category": "Algorithms & Computer Science",
    "file": "vcard-contact-generator.html",
    "path": "cards/vcard-contact-generator.html"
  },
  {
    "id": "venn-diagram-visualiser-title",
    "name": "venn-diagram-visualiser",
    "title": "🔵 Venn Diagram Visualiser",
    "description": "Type two lists and watch the Venn diagram draw itself — union, intersection, symmetric difference and per-zone items are listed.",
    "category": "Mathematics",
    "file": "venn-diagram-visualiser.html",
    "path": "cards/venn-diagram-visualiser.html"
  },
  {
    "id": "vibration-isolation-transmissibility-title",
    "name": "vibration-isolation-transmissibility",
    "title": "🛡️ Vibration Isolator Designer",
    "description": "Design mechanical vibration isolators and shock mounts using force transmissibility ($T_R$). Calculate required static deflection ($\\delta_{st}$), isolation efficiency ($\\eta$), and operating frequ...",
    "category": "Science & Engineering",
    "file": "vibration-isolation-transmissibility.html",
    "path": "cards/vibration-isolation-transmissibility.html"
  },
  {
    "id": "video-bitrate-file-size-calculator-title",
    "name": "video-bitrate-file-size-calculator",
    "title": "🎬 Video Bitrate File Size",
    "description": "Estimate video file size from duration and video/audio bitrates, or solve for the bitrate that fits a size budget. Formula: size ≈ (video + audio) × time. Container overhead is ignored.",
    "category": "Algorithms & Computer Science",
    "file": "video-bitrate-file-size-calculator.html",
    "path": "cards/video-bitrate-file-size-calculator.html"
  },
  {
    "id": "vo2max-title",
    "name": "vo2max",
    "title": "🏃 VO₂ Max Calculator",
    "description": "Estimate your VO₂ Max — a measure of aerobic fitness. The higher the value, the better your cardiovascular endurance.",
    "category": "Health & Fitness",
    "file": "vo2max.html",
    "path": "cards/vo2max.html"
  },
  {
    "id": "vocab-title",
    "name": "vocab",
    "title": "📝 Word List Flashcards",
    "description": "Build vocabulary with spaced repetition flashcards. Add words, quiz yourself, and track mastery.",
    "category": "Writing & Language",
    "file": "vocab.html",
    "path": "cards/vocab.html"
  },
  {
    "id": "vocabulary-trainer-title",
    "name": "vocabulary-trainer",
    "title": "Vocabulary Trainer",
    "description": "Add words with definitions and examples, practise with flashcards or quick quizzes, and track progress with simple Leitner boxes. Data is stored locally in this card.",
    "category": "Writing & Language",
    "file": "vocabulary-trainer.html",
    "path": "cards/vocabulary-trainer.html"
  },
  {
    "id": "volcanic-eruption-simulator-title",
    "name": "volcanic-eruption-simulator",
    "title": "🌋 Volcano Eruption Simulator",
    "description": "A living cross-section of a stratovolcano. Magma viscosity, dissolved gas, vent width and slope drive the real eruption style — Hawaiian fountains, Strombolian bursts or Plinian columns — with buoy...",
    "category": "Interactive Art & Living Worlds",
    "file": "volcanic-eruption-simulator.html",
    "path": "cards/volcanic-eruption-simulator.html"
  },
  {
    "id": "volleyball-score-sheet-title",
    "name": "volleyball-score-sheet",
    "title": "🏐 Volleyball Score Sheet & Rotation",
    "description": "Rally scoring to 25 (win by two, up to 30), with the fifth set to 15 — plus a rotation tracker: list your six players in serving order and they rotate every time the side that wins the rally was re...",
    "category": "Sports",
    "file": "volleyball-score-sheet.html",
    "path": "cards/volleyball-score-sheet.html"
  },
  {
    "id": "voltage-divider-calculator-title",
    "name": "voltage-divider-calculator",
    "title": "⚡ Voltage Divider",
    "description": "Vout = Vin × R2 / (R1 + R2). R1 is the top resistor from the supply; R2 is the bottom resistor to ground. Unloaded — a low-impedance load pulls the output down.",
    "category": "Science & Engineering",
    "file": "voltage-divider-calculator.html",
    "path": "cards/voltage-divider-calculator.html"
  },
  {
    "id": "voltage-drop-title",
    "name": "voltage-drop",
    "title": "⚡ Voltage Drop Calculator",
    "description": "Estimate voltage drop across a conductor run. Educational only — always verify with a qualified electrician and local standards.",
    "category": "Science & Engineering",
    "file": "voltage-drop.html",
    "path": "cards/voltage-drop.html"
  },
  {
    "id": "voxel-monolith-3d-time-capsule-title",
    "name": "voxel-monolith-3d-time-capsule",
    "title": "🗿 VoxelMonolith 3D",
    "description": "An isometric 3D voxel monument sculpted across time. Place obsidian, glowing crystal, gold, and marble blocks layer by layer. Scrub the chronological time slider to watch historical construction fr...",
    "category": "Interactive Art & Living Worlds",
    "file": "voxel-monolith-3d-time-capsule.html",
    "path": "cards/voxel-monolith-3d-time-capsule.html"
  },
  {
    "id": "waist-to-height-ratio-title",
    "name": "waist-to-height-ratio",
    "title": "📏 Waist-to-Height Ratio",
    "description": "NICE NG246 uses waist ÷ height as a central-adiposity screen for adults with BMI under 35. Measure the waist at the midpoint between the last rib and the hip bone. Not a diagnosis.",
    "category": "Health & Fitness",
    "file": "waist-to-height-ratio.html",
    "path": "cards/waist-to-height-ratio.html"
  },
  {
    "id": "waisthip-title",
    "name": "waisthip",
    "title": "📏 Waist-to-Hip Ratio Calculator",
    "description": "Calculate your waist-to-hip ratio and see your health risk category based on WHO guidelines.",
    "category": "Health & Fitness",
    "file": "waisthip.html",
    "path": "cards/waisthip.html"
  },
  {
    "id": "wall-anchor-guide-title",
    "name": "wall-anchor-guide",
    "title": "🔩 Wall Anchor Selector",
    "description": "Not sure what fixings to use? Tell us your wall type and what you're hanging — we'll tell you exactly what to buy.",
    "category": "Home & DIY",
    "file": "wall-anchor-guide.html",
    "path": "cards/wall-anchor-guide.html"
  },
  {
    "id": "wallpaper-estimator-title",
    "name": "wallpaper-estimator",
    "title": "🧻 Wallpaper Estimator",
    "description": "Calculate how many rolls of wallpaper you need — accounting for pattern repeat, doors, and windows.",
    "category": "Home & DIY",
    "file": "wallpaper-estimator.html",
    "path": "cards/wallpaper-estimator.html"
  },
  {
    "id": "water-density-anomaly-title",
    "name": "water-density-anomaly",
    "title": "💧 Water Density Anomaly Lab",
    "description": "Investigate water's famous thermodynamic density anomaly ($\\rho_{max}$ at $3.98^\\circ\\text{C}$). Explore negative thermal expansion, the $+9\\%$ ice phase transition volume expansion, and ecological...",
    "category": "Science & Engineering",
    "file": "water-density-anomaly.html",
    "path": "cards/water-density-anomaly.html"
  },
  {
    "id": "water-dielectric-dipole-relaxation-title",
    "name": "water-dielectric-dipole-relaxation",
    "title": "⚡ Water Dielectric Lab",
    "description": "Investigate water's molecular dipole moment ($\\mu = 1.854\\text{ Debye}$) and huge dielectric permittivity ($\\epsilon_r \\approx 80.1$). Model Debye relaxation ($\\epsilon^*(\\omega) = \\epsilon_\\infty ...",
    "category": "Science & Engineering",
    "file": "water-dielectric-dipole-relaxation.html",
    "path": "cards/water-dielectric-dipole-relaxation.html"
  },
  {
    "id": "water-hardness-langelier-index-title",
    "name": "water-hardness-langelier-index",
    "title": "🚰 Water Hardness (LSI) Lab",
    "description": "Assess water hardness and mineral stability using the Langelier Saturation Index ($\\text{LSI} = \\text{pH} - \\text{pH}_s$) and Ryznar Stability Index ($\\text{RSI}$). Predict calcium carbonate precip...",
    "category": "Science & Engineering",
    "file": "water-hardness-langelier-index.html",
    "path": "cards/water-hardness-langelier-index.html"
  },
  {
    "id": "water-ion-product-kw-ph-title",
    "name": "water-ion-product-kw-ph",
    "title": "🧪 Water Ionization & pH Lab",
    "description": "Investigate water's auto-protolysis equilibrium ($2\\text{H}_2\\text{O} \\rightleftharpoons \\text{H}_3\\text{O}^+ + \\text{OH}^-$). Discover why neutral water is $\\text{pH } 7.00$ only at $25^\\circ\\text...",
    "category": "Science & Engineering",
    "file": "water-ion-product-kw-ph.html",
    "path": "cards/water-ion-product-kw-ph.html"
  },
  {
    "id": "water-phase-diagram-title",
    "name": "water-phase-diagram",
    "title": "🏔️ Water Phase Diagram Lab",
    "description": "Navigate water's complete thermodynamic $P$-$T$ phase space across Solid, Liquid, Vapor, and Supercritical regimes. Explore the Triple Point ($0.01^\\circ\\text{C}, 611.65\\text{ Pa}$), Critical Point...",
    "category": "Science & Engineering",
    "file": "water-phase-diagram.html",
    "path": "cards/water-phase-diagram.html"
  },
  {
    "id": "water-purification-treatment-calculator-title",
    "name": "water-purification-treatment-calculator",
    "title": "💧 Water Purification Planner",
    "description": "You can live weeks without food and about three days without water. This works out how much to store, how many containers that is, and — the part people get wrong — exactly how to make a questionab...",
    "category": "Survival & Emergency Readiness",
    "file": "water-purification-treatment-calculator.html",
    "path": "cards/water-purification-treatment-calculator.html"
  },
  {
    "id": "water-surface-tension-capillary-title",
    "name": "water-surface-tension-capillary",
    "title": "🧪 Water Surface Tension Lab",
    "description": "Explore water's extraordinary cohesive hydrogen-bond surface tension ($\\sigma = 72.86\\text{ mN/m}$). Calculate Jurin's Law capillary rise ($h = \\frac{2\\sigma\\cos\\theta}{\\rho g r}$) and Young-Laplac...",
    "category": "Science & Engineering",
    "file": "water-surface-tension-capillary.html",
    "path": "cards/water-surface-tension-capillary.html"
  },
  {
    "id": "waterintake-title",
    "name": "waterintake",
    "title": "💧 Daily Water Intake Calculator",
    "description": "Estimate how much water you should drink each day based on your weight and activity level.",
    "category": "Health & Fitness",
    "file": "waterintake.html",
    "path": "cards/waterintake.html"
  },
  {
    "id": "wbtb-rem-sleep-calculator-title",
    "name": "wbtb-rem-sleep-calculator",
    "title": "🌙 WBTB Lucid Dream REM Planner",
    "description": "Wake-Back-To-Bed (WBTB) ultradian cycle planner based on Stanford sleep research. Targets Cycles 4 & 5 when REM duration and dream vividness peak by over 400%.",
    "category": "Lucid Dreaming & Sleep",
    "file": "wbtb-rem-sleep-calculator.html",
    "path": "cards/wbtb-rem-sleep-calculator.html"
  },
  {
    "id": "weightlifting-sinclair-score-title",
    "name": "weightlifting-sinclair-score",
    "title": "🏋️ Weightlifting Sinclair Score",
    "description": "The Sinclair coefficient lets lifters of different bodyweights be compared. Enter sex, bodyweight and total, and this computes the 2025–2028 Sinclair coefficient and Sinclair Total.",
    "category": "Sports",
    "file": "weightlifting-sinclair-score.html",
    "path": "cards/weightlifting-sinclair-score.html"
  },
  {
    "id": "what-year-are-you-title",
    "name": "what-year-are-you",
    "title": "Which Year Are You? 🕰️",
    "description": "Discover your internet personality era based on your tastes, habits, and vibes. ← Share your result!",
    "category": "Productivity & Lifestyle",
    "file": "what-year-are-you.html",
    "path": "cards/what-year-are-you.html"
  },
  {
    "id": "wheelbuilding-spoke-length-calculator-title",
    "name": "wheelbuilding-spoke-length-calculator",
    "title": "🛞 Wheelbuilding Spoke Length & Tension Calculator",
    "description": "Spoke length is a three-dimensional problem: the spoke runs from a hole in the hub flange, sideways to the rim centreline and around by however many crossings you lace. Get it wrong by two millimet...",
    "category": "Science & Engineering",
    "file": "wheelbuilding-spoke-length-calculator.html",
    "path": "cards/wheelbuilding-spoke-length-calculator.html"
  },
  {
    "id": "wholesale-pricing-margin-calculator-title",
    "name": "wholesale-pricing-margin-calculator",
    "title": "🏷️ Wholesale Pricing & Margin",
    "description": "Set retail and wholesale prices while seeing your margin and the retailer’s margin side by side. All calculations stay in your browser.",
    "category": "Finance & Money",
    "file": "wholesale-pricing-margin-calculator.html",
    "path": "cards/wholesale-pricing-margin-calculator.html"
  },
  {
    "id": "wifi-qr-generator-title",
    "name": "wifi-qr-generator",
    "title": "📶 Wi-Fi QR Pass Generator",
    "description": "Generate an instant, scannable QR code for your home, studio, or office Wi-Fi network. Guests can scan with their phone camera to connect immediately without typing complicated passwords. 🔒 Genuin...",
    "category": "Productivity & Lifestyle",
    "file": "wifi-qr-generator.html",
    "path": "cards/wifi-qr-generator.html"
  },
  {
    "id": "wifi-speed-bandwidth-calculator-title",
    "name": "wifi-speed-bandwidth-calculator",
    "title": "📶 WiFi Speed & Download Time Calculator",
    "description": "Calculate exact file download and upload durations, test bandwidth capacity for simultaneous 4K streams and video calls, and estimate mobile data cap exhaustion.",
    "category": "Algorithms & Computer Science",
    "file": "wifi-speed-bandwidth-calculator.html",
    "path": "cards/wifi-speed-bandwidth-calculator.html"
  },
  {
    "id": "wild-hypnagogia-tracker-title",
    "name": "wild-hypnagogia-tracker",
    "title": "🌀 WILD Hypnagogia Transition",
    "description": "Wake-Initiated Lucid Dreaming (WILD) mental anchor simulator. Ride the borderline hypnagogic transition directly from conscious waking state into full REM dream creation.",
    "category": "Lucid Dreaming & Sleep",
    "file": "wild-hypnagogia-tracker.html",
    "path": "cards/wild-hypnagogia-tracker.html"
  },
  {
    "id": "wildfire-behaviour-lab-title",
    "name": "wildfire-behaviour-lab",
    "title": "🔥 Wildfire Behaviour Lab",
    "description": "A fuel-bed cellular automaton with Rothermel-style spread. Set wind, fuel moisture, fuel load and slope, then click the terrain to ignite. Watch the fire front, smoke column, ember spotting and the...",
    "category": "Interactive Art & Living Worlds",
    "file": "wildfire-behaviour-lab.html",
    "path": "cards/wildfire-behaviour-lab.html"
  },
  {
    "id": "wind-chill-calculator-title",
    "name": "wind-chill-calculator",
    "title": "🌬️ Wind Chill Calculator",
    "description": "NWS/JAG/TI wind-chill (2001): valid when air is ≤ 10 °C and wind ≥ 4.8 km/h. It estimates how cold exposed skin feels — not a frostbite timer, and not for indoor fans.",
    "category": "Science & Engineering",
    "file": "wind-chill-calculator.html",
    "path": "cards/wind-chill-calculator.html"
  },
  {
    "id": "wind-triangle-flight-planner-title",
    "name": "wind-triangle-flight-planner",
    "title": "✈️ Wind Triangle & Flight Leg Planner",
    "description": "Air is a moving floor. Point the nose where you want to go and the wind quietly carries you somewhere else, so every navigation log starts with the same triangle. This solves it exactly — heading t...",
    "category": "Science & Engineering",
    "file": "wind-triangle-flight-planner.html",
    "path": "cards/wind-triangle-flight-planner.html"
  },
  {
    "id": "wind-wave-fetch-forecaster-title",
    "name": "wind-wave-fetch-forecaster",
    "title": "🌬️ Wind, Fetch & Wave Forecaster",
    "description": "Waves are built by three things: how hard the wind blows, how far it blows over open water, and how long it keeps blowing. This works out which of the three is holding your sea state back, using th...",
    "category": "Science & Engineering",
    "file": "wind-wave-fetch-forecaster.html",
    "path": "cards/wind-wave-fetch-forecaster.html"
  },
  {
    "id": "wire-gauge-title",
    "name": "wire-gauge",
    "title": "⚡ Wire Gauge Calculator",
    "description": "Professional wire sizing calculator for electrical installations with NEC/IEC compliance checks and safety recommendations.",
    "category": "Science & Engineering",
    "file": "wire-gauge.html",
    "path": "cards/wire-gauge.html"
  },
  {
    "id": "word-counter-title",
    "name": "word-counter",
    "title": "📝 Word Counter & Analyser",
    "description": "Count words, characters, sentences, and estimate reading time. Useful for essays and assignments.",
    "category": "Productivity & Lifestyle",
    "file": "word-counter.html",
    "path": "cards/word-counter.html"
  },
  {
    "id": "word-frequency-counter-title",
    "name": "word-frequency-counter",
    "title": "📊 Word Frequency Counter",
    "description": "Analyze text to find the most common words, unique words, and word frequency distribution with visual charts.",
    "category": "Writing & Language",
    "file": "word-frequency-counter.html",
    "path": "cards/word-frequency-counter.html"
  },
  {
    "id": "workhours-title",
    "name": "workhours",
    "title": "⏱️ Work Hours & Pay Calculator",
    "description": "Calculate work hours, breaks, overtime, and pay. Track multiple shifts, different pay rates, and generate detailed timesheets. Perfect for freelancers, contractors, and employees!",
    "category": "Productivity & Lifestyle",
    "file": "workhours.html",
    "path": "cards/workhours.html"
  },
  {
    "id": "world-capitals-quiz-title",
    "name": "world-capitals-quiz",
    "title": "🌍 World Capitals Quiz",
    "description": "Learn the world's capitals with multiple choice or typed answers, region filters, streak tracking and a little history with every question. 60 countries quizzed — nothing is sent anywhere, it all r...",
    "category": "MrProphecy Arcade",
    "file": "world-capitals-quiz.html",
    "path": "cards/world-capitals-quiz.html"
  },
  {
    "id": "worry-sorter-3am-title",
    "name": "worry-sorter-3am",
    "title": "🌙 The 3am Worry Sorter",
    "description": "For the thoughts that queue up at 3am. Tick what's rattling around, add your own, and this will sort each one into Do Now, Schedule, or Let Go — with a kind word for each. Nothing is saved.",
    "category": "Productivity & Lifestyle",
    "file": "worry-sorter-3am.html",
    "path": "cards/worry-sorter-3am.html"
  },
  {
    "id": "xmas-card-writer-assistant-title",
    "name": "xmas-card-writer-assistant",
    "title": "✍️ XMAS Card Writer Assistant",
    "description": "Struggling with what to write? Get personalized Christmas card messages for everyone on your list! Save time, spread joy!",
    "category": "Productivity & Lifestyle",
    "file": "xmas-card-writer-assistant.html",
    "path": "cards/xmas-card-writer-assistant.html"
  },
  {
    "id": "xmas-countdown-title",
    "name": "xmas-countdown",
    "title": "🎄 Christmas Countdown",
    "description": "Count down to Christmas with real-time tracking, festive facts, and daily suggestions! 🎅 Shows days, hours, minutes until Christmas morning",
    "category": "Productivity & Lifestyle",
    "file": "xmas-countdown.html",
    "path": "cards/xmas-countdown.html"
  },
  {
    "id": "xmas-gift-budget-title",
    "name": "xmas-gift-budget",
    "title": "💰 Christmas Gift Budget Planner",
    "description": "Plan, track, and optimize your Christmas gift spending. Avoid overspending with smart budgeting! ✅ Features: Gift ideas, price tracking, comparison shopping, receipt scanning",
    "category": "Finance & Money",
    "file": "xmas-gift-budget.html",
    "path": "cards/xmas-gift-budget.html"
  },
  {
    "id": "xmas-santa-tracker-title",
    "name": "xmas-santa-tracker",
    "title": "🎅 Santa Tracker & Message Center",
    "description": "Track Santa's journey and send him a message! Get a personalized response from the North Pole. Perfect for kids and kids-at-heart!",
    "category": "Productivity & Lifestyle",
    "file": "xmas-santa-tracker.html",
    "path": "cards/xmas-santa-tracker.html"
  },
  {
    "id": "xml-beautifier-formatter-title",
    "name": "xml-beautifier-formatter",
    "title": "🌳 XML Beautifier",
    "description": "Pretty-print or minify XML in the browser. No schema validation, no network. Attributes and comments are preserved as text — this is an indenter, not a full XML parser.",
    "category": "Algorithms & Computer Science",
    "file": "xml-beautifier-formatter.html",
    "path": "cards/xml-beautifier-formatter.html"
  },
  {
    "id": "xml-formatter-title",
    "name": "xml-formatter",
    "title": "📐 XML Formatter & Validator",
    "description": "Format, minify, validate, and explore XML. Paste messy XML, get clean indented output with syntax highlighting.",
    "category": "Algorithms & Computer Science",
    "file": "xml-formatter.html",
    "path": "cards/xml-formatter.html"
  },
  {
    "id": "yaml-converter-title",
    "name": "yaml-converter",
    "title": "📋 YAML ↔ JSON Converter",
    "description": "Convert between YAML and JSON instantly. Paste, convert, copy. Supports nested structures, arrays, and multi-line strings.",
    "category": "Algorithms & Computer Science",
    "file": "yaml-converter.html",
    "path": "cards/yaml-converter.html"
  },
  {
    "id": "yeast-fresh-instant-converter-title",
    "name": "yeast-fresh-instant-converter",
    "title": "🍞 Yeast Converter",
    "description": "Swap fresh cake yeast, active dry and instant/fast-action using the baker’s 1 : 1.25 : 3 rule (instant : active dry : fresh by weight). Teaspoons assume 3.1 g instant per level tsp.",
    "category": "Culinary & Food Science",
    "file": "yeast-fresh-instant-converter.html",
    "path": "cards/yeast-fresh-instant-converter.html"
  },
  {
    "id": "younger-futhark-runes-title",
    "name": "younger-futhark-runes",
    "title": "ᚠ The Rune Cabinet",
    "description": "Sixteen staves, not twenty-four. After about 700 CE the north dropped Elder Futhark down to this tighter case — one rune now stands for several Latin letters. Stones from Jelling to Rök speak it. T...",
    "category": "Museum & Collection",
    "file": "younger-futhark-runes.html",
    "path": "cards/younger-futhark-runes.html"
  },
  {
    "id": "youth-aesthetic-bio-title",
    "name": "youth-aesthetic-bio",
    "title": "✨ Aesthetic Bio Generator",
    "description": "Generate stylish bios for Instagram, TikTok, Discord, Twitter/X, and more — with fonts, symbols, and vibes",
    "category": "Writing & Language",
    "file": "youth-aesthetic-bio.html",
    "path": "cards/youth-aesthetic-bio.html"
  },
  {
    "id": "youth-caption-generator-title",
    "name": "youth-caption-generator",
    "title": "📱 Caption Generator",
    "description": "Generate Instagram, TikTok, and selfie captions — funny, aesthetic, savage, or wholesome",
    "category": "Writing & Language",
    "file": "youth-caption-generator.html",
    "path": "cards/youth-caption-generator.html"
  },
  {
    "id": "youth-color-palette-title",
    "name": "youth-color-palette",
    "title": "🎨 Aesthetic Color Palette Generator",
    "description": "Generate beautiful color palettes for designs, social media, and vibes — click to copy hex codes",
    "category": "Productivity & Lifestyle",
    "file": "youth-color-palette.html",
    "path": "cards/youth-color-palette.html"
  },
  {
    "id": "youth-gpa-calculator-title",
    "name": "youth-gpa-calculator",
    "title": "📊 GPA Calculator",
    "description": "Calculate your GPA, track grades, and see what you need to hit your target — supports US, UK, and percentage systems",
    "category": "Mathematics",
    "file": "youth-gpa-calculator.html",
    "path": "cards/youth-gpa-calculator.html"
  },
  {
    "id": "youth-money-tracker-title",
    "name": "youth-money-tracker",
    "title": "💸 Money Tracker",
    "description": "Track your spending, set a budget, and see where your money goes — simple enough for your first budget",
    "category": "Finance & Money",
    "file": "youth-money-tracker.html",
    "path": "cards/youth-money-tracker.html"
  },
  {
    "id": "youth-playlist-name-title",
    "name": "youth-playlist-name",
    "title": "🎵 Playlist Name Generator",
    "description": "Generate creative playlist names for Spotify, Apple Music, and YouTube — match the vibe of your music",
    "category": "Productivity & Lifestyle",
    "file": "youth-playlist-name.html",
    "path": "cards/youth-playlist-name.html"
  },
  {
    "id": "youth-resume-builder-title",
    "name": "youth-resume-builder",
    "title": "📄 First Resume Builder",
    "description": "Build your first CV or resume — even with no experience. Fill in what you have, get a clean, professional resume",
    "category": "Writing & Language",
    "file": "youth-resume-builder.html",
    "path": "cards/youth-resume-builder.html"
  },
  {
    "id": "youth-study-timer-title",
    "name": "youth-study-timer",
    "title": "📚 Study Timer (Pomodoro)",
    "description": "Focus timer with study/break cycles, session tracking, and motivational quotes — ace your exams",
    "category": "Productivity & Lifestyle",
    "file": "youth-study-timer.html",
    "path": "cards/youth-study-timer.html"
  },
  {
    "id": "youth-team-rotation-planner-title",
    "name": "youth-team-rotation-planner",
    "title": "👧 Youth Team Rotation Planner",
    "description": "Every child gets a fair go. Tell it how many players, how many are on the pitch at once, and how long the game lasts, and it builds a substitution plan that shares the minutes out as evenly as poss...",
    "category": "Sports",
    "file": "youth-team-rotation-planner.html",
    "path": "cards/youth-team-rotation-planner.html"
  },
  {
    "id": "youth-username-generator-title",
    "name": "youth-username-generator",
    "title": "🎮 Username Generator",
    "description": "Generate unique, cool usernames for gaming, social media, and streaming — check availability vibes",
    "category": "Productivity & Lifestyle",
    "file": "youth-username-generator.html",
    "path": "cards/youth-username-generator.html"
  },
  {
    "id": "youth-what-to-watch-title",
    "name": "youth-what-to-watch",
    "title": "🎬 What Should I Watch?",
    "description": "Can't decide what to watch? Answer 3 quick questions and get personalized movie/show recommendations",
    "category": "Productivity & Lifestyle",
    "file": "youth-what-to-watch.html",
    "path": "cards/youth-what-to-watch.html"
  },
  {
    "id": "youtube-dj-title",
    "name": "youtube-dj",
    "title": "🎛️ YouTube DJ Mixer",
    "description": "Mix YouTube videos live like a professional DJ. Crossfade between tracks, apply effects, and create seamless mixes. 🎧 Live mixing • Crossfader • EQ • Effects • YouTube integration",
    "category": "Music & Audio",
    "file": "youtube-dj.html",
    "path": "cards/youtube-dj.html"
  }
]