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HTML 

              
                <head>
  <meta charset="UTF-8">
  <title>Match Color CMYK</title>
  <script src="https://cdn.tailwindcss.com"></script>
  <style>
    body { transform-origin: top; transform: scale(1.25); }
  </style>
</head>
<body class="min-h-screen bg-neutral-500 text-gray-100 flex flex-col items-center py-8">
  <h1 class="text-3xl mb-2">Match Color CMYK</h1>
  <p class="mb-6 text-center">Guess the CMYK mix of the left swatch. Click "Compare colors" to reveal answer.</p>

  <!-- Swatches -->
  <div class="flex w-full max-w-lg h-40 rounded-lg overflow-hidden shadow-inner mb-8 relative">
    <div id="targetSwatch" class="flex-1"></div>
    <div class="w-px bg-neutral-600"></div>
    <div id="guessSwatch" class="flex-1"></div>
    <div id="accuracyOverlay" class="absolute inset-0 flex items-center justify-center text-white text-5xl drop-shadow-lg" style="display:none;"></div>
  </div>

  <!-- Sliders -->
  <div class="w-full max-w-lg space-y-6 mb-6">
    <div>
      <div class="flex justify-between mb-1">
        <span>Cyan ↔ Red</span>
        <span id="cLabel" class="font-mono">0%</span>
      </div>
      <input id="cSlider" type="range" min="-100" max="100" value="0" class="w-full accent-neutral-700">
    </div>
    <div>
      <div class="flex justify-between mb-1">
        <span>Magenta ↔ Green</span>
        <span id="mLabel" class="font-mono">0%</span>
      </div>
      <input id="mSlider" type="range" min="-100" max="100" value="0" class="w-full accent-neutral-700">
    </div>
    <div>
      <div class="flex justify-between mb-1">
        <span>Yellow ↔ Blue</span>
        <span id="yLabel" class="font-mono">0%</span>
      </div>
      <input id="ySlider" type="range" min="-100" max="100" value="0" class="w-full accent-neutral-700">
    </div>
    <div>
      <div class="flex justify-between mb-1">
        <span>Black</span>
        <span id="kLabel" class="font-mono">0%</span>
      </div>
      <input id="kSlider" type="range" min="-100" max="100" value="0" class="w-full accent-neutral-700">
    </div>
  </div>

  <!-- Buttons -->
  <div class="w-full max-w-lg mb-4">
    <button id="compareBtn" class="w-full bg-blue-500 text-white py-2 rounded">Compare colors</button>
  </div>
  <div class="w-full max-w-lg">
    <button id="resetBtn" class="w-full bg-neutral-700 text-white py-2 rounded">Try again</button>
  </div>

<script>
document.addEventListener('DOMContentLoaded', () => {
  // Utility
  const rnd = (min,max) => Math.floor(Math.random()*(max-min+1))+min;
  const clamp = (n,min,max) => Math.min(max, Math.max(min, n));
  const cmykToRgb = (c,m,y,k) => { c/=100; m/=100; y/=100; k/=100; return {r:255*(1-c)*(1-k), g:255*(1-m)*(1-k), b:255*(1-y)*(1-k)}; };
  const toCss = rgb => `rgb(${Math.round(rgb.r)}, ${Math.round(rgb.g)}, ${Math.round(rgb.b)})`;
  const sliderToPerc = v => clamp((v+100)/2, 0, 100);
  const percToSlider = p => clamp(Math.round(p*2 - 100), -100, 100);

  // Elements
  const keys = ['c','m','y','k'];
  const sliders = keys.map(k => document.getElementById(k+'Slider'));
  const labels = keys.map(k => document.getElementById(k+'Label'));
  const targetSwatch = document.getElementById('targetSwatch');
  const guessSwatch = document.getElementById('guessSwatch');
  const overlay = document.getElementById('accuracyOverlay');
  const compareBtn = document.getElementById('compareBtn');
  const resetBtn = document.getElementById('resetBtn');

  let target = {};
  let answered = false;

  // Update slider label
  function updateLabel(i) {
    const sliderVal = parseInt(sliders[i].value, 10);
    const guessPerc = sliderToPerc(sliderVal);
    if (answered) {
      const correctSlider = percToSlider(target[keys[i]]);
      labels[i].innerHTML = `${sliderVal}% / <span class="text-green-400">${correctSlider}%</span>`;
    } else {
      labels[i].textContent = `${sliderVal}%`;
    }
  }

  // Compute match percentage
  function updateAccuracy(guess) {
    const tgtRgb = cmykToRgb(target.c, target.m, target.y, target.k);
    const curRgb = cmykToRgb(guess.c, guess.m, guess.y, guess.k);
    const dr = tgtRgb.r - curRgb.r;
    const dg = tgtRgb.g - curRgb.g;
    const db = tgtRgb.b - curRgb.b;
    const dist = Math.sqrt(dr*dr + dg*dg + db*db);
    const maxDist = Math.sqrt(255*255*3);
    const pct = clamp(Math.round((1 - dist/maxDist) * 100), 0, 100);
    overlay.textContent = `${pct}% Match`;
  }

  // Render swatches
  function updateSwatches() {
    // Left: target
    targetSwatch.style.backgroundColor = toCss(cmykToRgb(target.c, target.m, target.y, target.k));
    // Right: guess
    const guess = {};
    keys.forEach((k,i) => { guess[k] = sliderToPerc(parseInt(sliders[i].value, 10)); });
    guessSwatch.style.backgroundColor = toCss(cmykToRgb(guess.c, guess.m, guess.y, guess.k));
    if (answered) updateAccuracy(guess);
  }

  // Initialize
  function init() {
    answered = false;
    overlay.style.display = 'none';
    // Random target
    keys.forEach(k => { target[k] = rnd(0, k==='k'?50:100); });
    // Random initial guess around target ±20%
    keys.forEach((k,i) => {
      const randomPerc = clamp(target[k] + rnd(-20, 20), 0, k==='k'?50:100);
      sliders[i].value = percToSlider(randomPerc);
      updateLabel(i);
    });
    updateSwatches();
  }

  // Events
  sliders.forEach((s,i) => s.addEventListener('input', () => { updateLabel(i); updateSwatches(); }));
  compareBtn.addEventListener('click', () => {
    answered = true;
    overlay.style.display = 'flex';
    // update labels to show correct slider values
    sliders.forEach((_, i) => updateLabel(i));
    // update swatches and compute match percentage
    updateSwatches();
  });
  resetBtn.addEventListener('click', init);

  init();
});
</script>
</body>
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