<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <meta name="aspect-ratio" content="4:3">
  <style>
    * {
      box-sizing: border-box;
      margin: 0;
      padding: 0;
    }
    body {
      font-family: system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
      background: #f8fafc;
      color: #1e293b;
      padding: 12px;
      display: flex;
      flex-direction: column;
      gap: 12px;
      min-height: 100%;
      user-select: none;
    }

    /* Builders Row */
    .builders-grid {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 10px;
    }
    .builder-card {
      background: #ffffff;
      border: 1.5px solid #e2e8f0;
      border-radius: 12px;
      padding: 10px 8px;
      display: flex;
      flex-direction: column;
      align-items: center;
      text-align: center;
      box-shadow: 0 1px 3px rgba(0,0,0,0.04);
    }
    .builder-card.tall { border-top: 4px solid #2563eb; }
    .builder-card.short { border-top: 4px solid #0d9488; }

    .avatar-row {
      display: flex;
      align-items: baseline;
      gap: 6px;
      margin-bottom: 4px;
    }
    .avatar-tall { font-size: 34px; line-height: 1; }
    .avatar-short { font-size: 26px; line-height: 1; }

    .builder-title {
      font-weight: 700;
      font-size: 13px;
      color: #334155;
    }

    /* Arm Measurement Visual */
    .cubit-measure {
      width: 100%;
      max-width: 200px;
      background: #f1f5f9;
      border-radius: 6px;
      padding: 6px 8px;
      margin-top: 6px;
      display: flex;
      flex-direction: column;
      align-items: center;
      gap: 4px;
    }
    .arm-svg {
      width: 100%;
      height: 24px;
    }
    .cubit-val {
      font-size: 12px;
      font-weight: 800;
    }
    .tall .cubit-val { color: #2563eb; }
    .short .cubit-val { color: #0d9488; }

    /* Comparison Section */
    .comparison-panel {
      background: #ffffff;
      border: 1.5px solid #e2e8f0;
      border-radius: 12px;
      padding: 12px 10px;
      display: flex;
      flex-direction: column;
      gap: 10px;
      box-shadow: 0 1px 3px rgba(0,0,0,0.04);
    }

    .order-badge {
      align-self: center;
      background: #f8fafc;
      border: 1px solid #cbd5e1;
      padding: 3px 12px;
      border-radius: 20px;
      font-size: 12px;
      font-weight: 700;
      color: #475569;
    }

    .plank-row {
      display: flex;
      flex-direction: column;
      gap: 3px;
    }
    .plank-label {
      font-size: 11px;
      font-weight: 600;
      color: #64748b;
      display: flex;
      justify-content: space-between;
    }

    .track {
      position: relative;
      width: 100%;
      height: 36px;
      background: #f1f5f9;
      border-radius: 6px;
      overflow: hidden;
      display: flex;
    }

    .plank {
      height: 100%;
      background: repeating-linear-gradient(
        90deg,
        #b45309 0px,
        #b45309 calc(10% - 1.5px),
        #92400e calc(10% - 1.5px),
        #92400e 10%
      );
      display: flex;
      align-items: center;
      justify-content: center;
      color: #fff;
      font-weight: 700;
      font-size: 11px;
      text-shadow: 0 1px 2px rgba(0,0,0,0.4);
      border-radius: 4px;
      transition: width 0.4s ease;
    }

    .plank-tall {
      width: 100%;
      background: repeating-linear-gradient(
        90deg,
        #b45309 0px,
        #b45309 calc(10% - 1.5px),
        #78350f calc(10% - 1.5px),
        #78350f 10%
      );
    }

    .plank-short {
      width: 80%;
      background: repeating-linear-gradient(
        90deg,
        #d97706 0px,
        #d97706 calc(10% - 1.5px),
        #92400e calc(10% - 1.5px),
        #92400e 10%
      );
    }

    /* Mismatched Gap */
    .gap-zone {
      width: 20%;
      height: 100%;
      background: repeating-linear-gradient(
        45deg,
        #fee2e2,
        #fee2e2 6px,
        #fecaca 6px,
        #fecaca 12px
      );
      border: 2px dashed #ef4444;
      border-left: none;
      display: flex;
      align-items: center;
      justify-content: center;
      box-sizing: border-box;
      border-radius: 0 4px 4px 0;
    }
    .gap-icon {
      font-size: 16px;
      font-weight: 900;
      color: #dc2626;
      animation: pulse 1.8s infinite ease-in-out;
    }

    @keyframes pulse {
      0%, 100% { transform: scale(1); opacity: 1; }
      50% { transform: scale(1.2); opacity: 0.8; }
    }

    .mismatch-alert {
      background: #fef2f2;
      border: 1.5px solid #fecaca;
      color: #b91c1c;
      font-weight: 700;
      font-size: 12px;
      text-align: center;
      padding: 6px 10px;
      border-radius: 8px;
      display: flex;
      align-items: center;
      justify-content: center;
      gap: 6px;
    }
  </style>
</head>
<body>

  
  <div class="builders-grid">
    <div class="builder-card tall">
      <div class="avatar-row">
        <span class="avatar-tall">🧔‍♂️</span>
        <span class="builder-title">Tall Builder</span>
      </div>
      <div class="cubit-measure">
        <svg class="arm-svg" viewBox="0 0 140 20">
          <line x1="10" y1="10" x2="130" y2="10" stroke="#2563eb" stroke-width="3" stroke-linecap="round"/>
          <line x1="10" y1="4" x2="10" y2="16" stroke="#2563eb" stroke-width="2.5" stroke-linecap="round"/>
          <line x1="130" y1="4" x2="130" y2="16" stroke="#2563eb" stroke-width="2.5" stroke-linecap="round"/>
          <circle cx="10" cy="10" r="3" fill="#2563eb"/>
          <path d="M 125 7 L 133 10 L 125 13" fill="none" stroke="#2563eb" stroke-width="2" stroke-linejoin="round"/>
        </svg>
        <span class="cubit-val">1 cubit = 20 in</span>
      </div>
    </div>

    <div class="builder-card short">
      <div class="avatar-row">
        <span class="avatar-short">👦</span>
        <span class="builder-title">Short Builder</span>
      </div>
      <div class="cubit-measure">
        <svg class="arm-svg" viewBox="0 0 140 20">
          <line x1="25" y1="10" x2="115" y2="10" stroke="#0d9488" stroke-width="3" stroke-linecap="round"/>
          <line x1="25" y1="4" x2="25" y2="16" stroke="#0d9488" stroke-width="2.5" stroke-linecap="round"/>
          <line x1="115" y1="4" x2="115" y2="16" stroke="#0d9488" stroke-width="2.5" stroke-linecap="round"/>
          <circle cx="25" cy="10" r="3" fill="#0d9488"/>
          <path d="M 110 7 L 118 10 L 110 13" fill="none" stroke="#0d9488" stroke-width="2" stroke-linejoin="round"/>
        </svg>
        <span class="cubit-val">1 cubit = 16 in</span>
      </div>
    </div>
  </div>

  
  <div class="comparison-panel">
    <div class="order-badge">📦 Order: "10 cubits long"</div>

    
    <div class="plank-row">
      <div class="plank-label">
        <span>Tall Plank (10 × 20 in)</span>
        <b>200 in</b>
      </div>
      <div class="track">
        <div class="plank plank-tall">10 Cubits</div>
      </div>
    </div>

    
    <div class="plank-row">
      <div class="plank-label">
        <span>Short Plank (10 × 16 in)</span>
        <b>160 in</b>
      </div>
      <div class="track">
        <div class="plank plank-short">10 Cubits</div>
        <div class="gap-zone">
          <span class="gap-icon">❓</span>
        </div>
      </div>
    </div>

    
    <div class="mismatch-alert">
      <span>⚠️</span>
      <span>Different sizes = mismatched pieces!</span>
    </div>
  </div>

</body>
</html>

Ancient Body-Based Units and the Need for Standardization

<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <meta name="aspect-ratio" content="1:1">
  <style>
    * {
      box-sizing: border-box;
      margin: 0;
      padding: 0;
      user-select: none;
    }
    body {
      width: 100%;
      height: 100%;
      background: #ffffff;
      font-family: system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
      display: flex;
      flex-direction: column;
      align-items: center;
      justify-content: center;
      padding: 8px;
    }
    .svg-container {
      width: 100%;
      max-width: 440px;
      aspect-ratio: 1 / 1;
      position: relative;
    }
    svg {
      width: 100%;
      height: 100%;
      display: block;
      overflow: visible;
    }
    .toggle-bar {
      margin-top: 6px;
      display: flex;
      gap: 6px;
      background: #f1f5f9;
      padding: 3px;
      border-radius: 20px;
    }
    .toggle-btn {
      border: none;
      background: transparent;
      padding: 5px 12px;
      border-radius: 16px;
      font-size: 13px;
      font-weight: 600;
      color: #64748b;
      cursor: pointer;
      transition: all 0.25s ease;
    }
    .toggle-btn.active {
      background: #ffffff;
      color: #0f172a;
      box-shadow: 0 1px 4px rgba(0,0,0,0.12);
    }
    .guide-line {
      stroke: #0284c7;
      stroke-dasharray: 4 3;
      stroke-width: 1.5;
      opacity: 0.7;
    }
    .rod-transition {
      transition: all 0.5s cubic-bezier(0.4, 0, 0.2, 1);
    }
  </style>
</head>
<body>

  <div class="svg-container">
    <svg viewBox="0 0 400 400">
      <defs>
        
        <linearGradient id="granite" x1="0%" y1="0%" x2="100%" y2="100%">
          <stop offset="0%" stop-color="#1e293b"/>
          <stop offset="50%" stop-color="#334155"/>
          <stop offset="100%" stop-color="#0f172a"/>
        </linearGradient>

        
        <linearGradient id="woodA" x1="0%" y1="0%" x2="100%" y2="0%">
          <stop offset="0%" stop-color="#b45309"/>
          <stop offset="50%" stop-color="#d97706"/>
          <stop offset="100%" stop-color="#92400e"/>
        </linearGradient>

        
        <linearGradient id="limestone" x1="0%" y1="0%" x2="0%" y2="100%">
          <stop offset="0%" stop-color="#f8fafc"/>
          <stop offset="100%" stop-color="#cbd5e1"/>
        </linearGradient>

        
        <marker id="arrow" viewBox="0 0 10 10" refX="6" refY="5" markerWidth="6" markerHeight="6" orient="auto-start-reverse">
          <path d="M 0 1 L 8 5 L 0 9 z" fill="#0284c7"/>
        </marker>
      </defs>

      
      <line id="guideL" x1="60" y1="52" x2="60" y2="330" class="guide-line"/>
      <line id="guideR" x1="340" y1="52" x2="340" y2="330" class="guide-line"/>

      
      <g transform="translate(0, 18)">
        <text x="200" y="16" text-anchor="middle" font-size="14" font-weight="700" fill="#0f172a" letter-spacing="0.2">
          Pharaoh's Royal Master Rod
        </text>
        <text x="200" y="32" text-anchor="middle" font-size="11" font-weight="600" fill="#64748b">
          Dark Granite • 28 Marked Digits
        </text>

        
        <rect x="60" y="40" width="280" height="24" rx="4" fill="url(#granite)" stroke="#0f172a" stroke-width="1.5"/>
        
        
        <g stroke="#fbbf24" stroke-width="1" opacity="0.85">
          
          <g id="masterTicks"></g>
        </g>
        
        <rect x="59" y="39" width="3" height="26" rx="1" fill="#f59e0b"/>
        <rect x="338" y="39" width="3" height="26" rx="1" fill="#f59e0b"/>
      </g>

      
      <path d="M 150 94 L 115 140" fill="none" stroke="#0284c7" stroke-width="2" marker-end="url(#arrow)"/>
      <path d="M 250 94 L 285 140" fill="none" stroke="#0284c7" stroke-width="2" marker-end="url(#arrow)"/>
      <text x="200" y="120" text-anchor="middle" font-size="11" font-weight="700" fill="#0284c7">
        Standard Copies
      </text>

      
      
      <g id="groupRodA" class="rod-transition" transform="translate(0, 0)">
        <text id="lblRodA" x="120" y="162" text-anchor="middle" font-size="13" font-weight="700" fill="#92400e">
          Site Rod A (Wood)
        </text>
        <rect id="rodABox" x="60" y="170" width="125" height="18" rx="3" fill="url(#woodA)" stroke="#78350f" stroke-width="1"/>
        <g id="rodATicks" stroke="#fef3c7" stroke-width="0.75" opacity="0.8"></g>
      </g>

      
      <g id="groupRodB" class="rod-transition" transform="translate(0, 0)">
        <text id="lblRodB" x="280" y="162" text-anchor="middle" font-size="13" font-weight="700" fill="#92400e">
          Site Rod B (Wood)
        </text>
        <rect id="rodBBox" x="215" y="170" width="125" height="18" rx="3" fill="url(#woodA)" stroke="#78350f" stroke-width="1"/>
        <g id="rodBTicks" stroke="#fef3c7" stroke-width="0.75" opacity="0.8"></g>
      </g>

      
      <g id="equalityBadge" transform="translate(200, 206)">
        <rect x="-65" y="-12" width="130" height="24" rx="12" fill="#ecfdf5" stroke="#10b981" stroke-width="1.5"/>
        <text id="equalityText" x="0" y="4" text-anchor="middle" font-size="12" font-weight="700" fill="#047857">
          ✓ Exact Match
        </text>
      </g>

      
      <g transform="translate(0, 238)">
        <text x="200" y="16" text-anchor="middle" font-size="13" font-weight="700" fill="#334155">
          Pyramid Stone Blocks
        </text>

        
        <rect id="blockA" class="rod-transition" x="60" y="24" width="138" height="68" rx="2" fill="url(#limestone)" stroke="#64748b" stroke-width="1.5"/>
        
        <line x1="85" y1="42" x2="105" y2="42" stroke="#94a3b8" stroke-width="1"/>
        <line x1="130" y1="65" x2="160" y2="65" stroke="#94a3b8" stroke-width="1"/>

        
        <rect id="blockB" class="rod-transition" x="202" y="24" width="138" height="68" rx="2" fill="url(#limestone)" stroke="#64748b" stroke-width="1.5"/>
        
        <line x1="230" y1="58" x2="255" y2="58" stroke="#94a3b8" stroke-width="1"/>
        <line x1="280" y1="40" x2="310" y2="40" stroke="#94a3b8" stroke-width="1"/>

        
        <g id="fitIndicator" transform="translate(200, 58)">
          <circle cx="0" cy="0" r="13" fill="#10b981"/>
          <text x="0" y="4" text-anchor="middle" font-size="13" font-weight="800" fill="#ffffff">✓</text>
          <text id="fitLabel" x="0" y="45" text-anchor="middle" font-size="12" font-weight="700" fill="#047857">
            Perfect Seamless Fit
          </text>
        </g>
      </g>
    </svg>
  </div>

  
  <div class="toggle-bar">
    <button id="btnStandard" class="toggle-btn active" onclick="setMode('standard')">Standardized Master</button>
    <button id="btnVariable" class="toggle-btn" onclick="setMode('variable')">Unstandardized Arms</button>
  </div>

  <script>
    // Render 28 Digit ticks on granite master rod (28 segments = 27 tick lines)
    const masterTicksG = document.getElementById('masterTicks');
    const rodATicksG = document.getElementById('rodATicks');
    const rodBTicksG = document.getElementById('rodBTicks');

    function drawTicks(container, startX, width, count, y1, y2) {
      container.innerHTML = '';
      const step = width / count;
      for (let i = 1; i < count; i++) {
        const x = startX + i * step;
        const line = document.createElementNS('http://www.w3.org/2000/svg', 'line');
        line.setAttribute('x1', x);
        line.setAttribute('x2', x);
        line.setAttribute('y1', y1);
        line.setAttribute('y2', y2);
        // Every 4 digits (1 palm) make a longer line
        if (i % 4 === 0) {
          line.setAttribute('stroke-width', '1.5');
          line.setAttribute('opacity', '1');
        }
        container.appendChild(line);
      }
    }

    drawTicks(masterTicksG, 60, 280, 28, 40, 64);
    drawTicks(rodATicksG, 60, 125, 14, 170, 188);
    drawTicks(rodBTicksG, 215, 125, 14, 170, 188);

    function setMode(mode) {
      const isStd = mode === 'standard';
      document.getElementById('btnStandard').classList.toggle('active', isStd);
      document.getElementById('btnVariable').classList.toggle('active', !isStd);

      const rodABox = document.getElementById('rodABox');
      const rodBBox = document.getElementById('rodBBox');
      const blockA = document.getElementById('blockA');
      const blockB = document.getElementById('blockB');
      const fitCircle = document.querySelector('#fitIndicator circle');
      const fitIcon = document.querySelector('#fitIndicator text');
      const fitLabel = document.getElementById('fitLabel');
      const eqBadge = document.querySelector('#equalityBadge rect');
      const eqText = document.getElementById('equalityText');

      if (isStd) {
        // Standardized
        rodABox.setAttribute('width', '125');
        rodBBox.setAttribute('x', '215');
        rodBBox.setAttribute('width', '125');
        drawTicks(rodATicksG, 60, 125, 14, 170, 188);
        drawTicks(rodBTicksG, 215, 125, 14, 170, 188);

        blockA.setAttribute('width', '138');
        blockB.setAttribute('x', '202');
        blockB.setAttribute('width', '138');

        fitCircle.setAttribute('fill', '#10b981');
        fitIcon.textContent = '✓';
        fitLabel.textContent = 'Perfect Seamless Fit';
        fitLabel.setAttribute('fill', '#047857');

        eqBadge.setAttribute('fill', '#ecfdf5');
        eqBadge.setAttribute('stroke', '#10b981');
        eqText.textContent = '✓ Exact Match';
        eqText.setAttribute('fill', '#047857');
      } else {
        // Variable Arms (Misalignment / Gap demonstration)
        rodABox.setAttribute('width', '95');  // Worker A has short arms
        rodBBox.setAttribute('x', '195');
        rodBBox.setAttribute('width', '145'); // Worker B has long arms
        drawTicks(rodATicksG, 60, 95, 14, 170, 188);
        drawTicks(rodBTicksG, 195, 145, 14, 170, 188);

        blockA.setAttribute('width', '108');
        blockB.setAttribute('x', '230');
        blockB.setAttribute('width', '138');

        fitCircle.setAttribute('fill', '#ef4444');
        fitIcon.textContent = '✗';
        fitLabel.textContent = 'Mismatched Gap & Error';
        fitLabel.setAttribute('fill', '#b91c1c');

        eqBadge.setAttribute('fill', '#fef2f2');
        eqBadge.setAttribute('stroke', '#ef4444');
        eqText.textContent = '✗ Different Lengths';
        eqText.setAttribute('fill', '#b91c1c');
      }
    }
  </script>
</body>
</html>

<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <style>
    * { box-sizing: border-box; margin: 0; padding: 0; }
    body {
      font-family: system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
      color: #1e2945;
      background: transparent;
      width: 100%;
      display: flex;
      flex-direction: column;
      align-items: center;
      justify-content: center;
      padding: 10px 8px;
      user-select: none;
    }

    .main-grid {
      display: grid;
      grid-template-columns: 1.15fr 0.85fr;
      gap: 16px;
      width: 100%;
      max-width: 580px;
      align-items: center;
    }

    @media (max-width: 480px) {
      .main-grid {
        grid-template-columns: 1fr;
        gap: 12px;
      }
    }

    /* SVG Canvas Container - Clean, no nested box */
    .figure-container {
      position: relative;
      background: transparent;
      border: none;
      box-shadow: none;
      padding: 4px;
      display: flex;
      justify-content: center;
      align-items: center;
    }

    svg {
      width: 100%;
      height: auto;
      max-height: 295px;
      display: block;
      overflow: visible;
    }

    /* Unit Buttons List */
    .units-list {
      display: flex;
      flex-direction: column;
      gap: 8px;
    }

    .unit-card {
      display: flex;
      align-items: center;
      justify-content: space-between;
      padding: 8px 12px;
      background: #ffffff;
      border-radius: 10px;
      border: 2px solid #e2e8f0;
      cursor: pointer;
      transition: border-color 0.2s ease, box-shadow 0.2s ease, background-color 0.2s ease;
    }

    .unit-card:hover {
      box-shadow: 0 2px 6px rgba(0,0,0,0.06);
      border-color: #cbd5e1;
    }

    .unit-card.active {
      border-color: var(--theme-color);
      background: #ffffff;
      box-shadow: 0 0 0 1px var(--theme-color), 0 3px 10px var(--glow-color);
    }

    .card-left {
      display: flex;
      align-items: center;
      gap: 10px;
    }

    .card-icon {
      font-size: 18px;
      width: 32px;
      height: 32px;
      display: flex;
      align-items: center;
      justify-content: center;
      border-radius: 8px;
      background: var(--bg-light);
      flex-shrink: 0;
    }

    .card-title {
      font-size: 14px;
      font-weight: 700;
      color: #1e2945;
    }

    .card-val {
      font-size: 13px;
      font-weight: 600;
      color: #64748b;
    }

    .unit-card.active .card-val {
      color: var(--theme-color);
      font-weight: 700;
    }

    /* Interactive highlight overlays */
    .hl-bracket {
      transition: opacity 0.25s ease, filter 0.25s ease;
      opacity: 0.35;
      cursor: pointer;
    }

    .hl-bracket:hover {
      opacity: 0.75;
    }

    .hl-bracket.active {
      opacity: 1;
      filter: drop-shadow(0 2px 4px rgba(0,0,0,0.15));
    }

    .badge-bg {
      filter: drop-shadow(0 1.5px 3px rgba(0,0,0,0.2));
    }
  </style>
</head>
<body>

<div class="main-grid">
  
  <div class="figure-container">
    <svg viewBox="0 0 320 300" aria-label="Ancient Body Units Diagram">
      <defs>
        
        <marker id="m-blue" viewBox="0 0 6 6" refX="3" refY="3" markerWidth="4" markerHeight="4" orient="auto">
          <circle cx="3" cy="3" r="2.5" fill="#0369a1"/>
        </marker>
        <marker id="m-teal" viewBox="0 0 6 6" refX="3" refY="3" markerWidth="4" markerHeight="4" orient="auto">
          <circle cx="3" cy="3" r="2.5" fill="#0f766e"/>
        </marker>
        <marker id="m-purple" viewBox="0 0 6 6" refX="3" refY="3" markerWidth="4" markerHeight="4" orient="auto">
          <circle cx="3" cy="3" r="2.5" fill="#6d28d9"/>
        </marker>
        <marker id="m-orange" viewBox="0 0 6 6" refX="3" refY="3" markerWidth="4" markerHeight="4" orient="auto">
          <circle cx="3" cy="3" r="2.5" fill="#c2410c"/>
        </marker>
      </defs>

      
      <g fill="#cbd5e1" stroke="#94a3b8" stroke-width="1.5" stroke-linejoin="round">
        
        <circle cx="145" cy="32" r="14" />
        
        
        <path d="M 134 48 L 156 48 L 152 135 L 138 135 Z" />
        
        
        <path d="M 134 50 L 98 75" stroke-linecap="round" fill="none" stroke-width="8.5" stroke="#cbd5e1" />
        <path d="M 98 75 L 68 95" stroke-linecap="round" fill="none" stroke-width="7.5" stroke="#cbd5e1" />
        
        <path d="M 68 95 L 50 78" stroke-linecap="round" fill="none" stroke-width="4.5" stroke="#cbd5e1" /> 
        <path d="M 68 95 L 44 92" stroke-linecap="round" fill="none" stroke-width="4.5" stroke="#cbd5e1" /> 
        <path d="M 68 95 L 50 110" stroke-linecap="round" fill="none" stroke-width="4.5" stroke="#cbd5e1" /> 
        
        
        
        <path d="M 156 50 L 186 80" stroke-linecap="round" fill="none" stroke-width="8.5" stroke="#cbd5e1" />
        
        <path d="M 186 80 L 226 54" stroke-linecap="round" fill="none" stroke-width="7.5" stroke="#cbd5e1" />
        
        <ellipse cx="232" cy="49" rx="6" ry="7" transform="rotate(-30 232 49)" fill="#cbd5e1" stroke="none" />
        <path d="M 233 48 L 244 38" stroke-linecap="round" fill="none" stroke-width="4" stroke="#cbd5e1" />

        
        
        <path d="M 140 135 L 110 195 L 82 256" stroke-linecap="round" stroke-linejoin="round" fill="none" stroke-width="9.5" stroke="#cbd5e1" />
        <path d="M 82 256 L 66 258" stroke-linecap="round" fill="none" stroke-width="7.5" stroke="#cbd5e1" />

        
        <path d="M 150 135 L 175 195 L 208 256" stroke-linecap="round" stroke-linejoin="round" fill="none" stroke-width="9.5" stroke="#cbd5e1" />
        <path d="M 208 256 L 228 258" stroke-linecap="round" fill="none" stroke-width="7.5" stroke="#cbd5e1" />
      </g>

      

      
      <g id="br-digit" class="hl-bracket active" onclick="selectUnit('digit')">
        
        <circle cx="244" cy="38" r="6" fill="none" stroke="#0369a1" stroke-width="2" />
        <line x1="240" y1="33" x2="248" y2="43" stroke="#0369a1" stroke-width="2" />
        <path d="M 249 34 L 260 22" stroke="#0369a1" stroke-width="1.75" stroke-dasharray="2 2" />
        <rect class="badge-bg" x="256" y="10" width="54" height="22" rx="6" fill="#0369a1" />
        <text x="283" y="22" font-size="11.5" font-weight="700" fill="#ffffff" text-anchor="middle" dominant-baseline="central">Digit</text>
      </g>

      
      <g id="br-span" class="hl-bracket" onclick="selectUnit('span')">
        <path d="M 46 76 L 46 112" stroke="#0f766e" stroke-width="2.5" marker-start="url(#m-teal)" marker-end="url(#m-teal)" />
        <path d="M 46 94 L 38 94" stroke="#0f766e" stroke-width="1.75" stroke-dasharray="2 2" />
        <rect class="badge-bg" x="4" y="83" width="50" height="22" rx="6" fill="#0f766e" />
        <text x="29" y="95" font-size="11.5" font-weight="700" fill="#ffffff" text-anchor="middle" dominant-baseline="central">Span</text>
      </g>

      
      <g id="br-cubit" class="hl-bracket" onclick="selectUnit('cubit')">
        <path d="M 183 90 L 236 55" stroke="#6d28d9" stroke-width="2.5" marker-start="url(#m-purple)" marker-end="url(#m-purple)" />
        <path d="M 208 73 L 216 86" stroke="#6d28d9" stroke-width="1.75" stroke-dasharray="2 2" />
        <rect class="badge-bg" x="195" y="88" width="52" height="22" rx="6" fill="#6d28d9" />
        <text x="221" y="100" font-size="11.5" font-weight="700" fill="#ffffff" text-anchor="middle" dominant-baseline="central">Cubit</text>
      </g>

      
      <g id="br-pace" class="hl-bracket" onclick="selectUnit('pace')">
        
        <line x1="45" y1="262" x2="245" y2="262" stroke="#e2e8f0" stroke-width="1.5" />
        
        <path d="M 66 278 L 228 278" stroke="#c2410c" stroke-width="2" marker-start="url(#m-orange)" marker-end="url(#m-orange)" />
        
        <line x1="66" y1="258" x2="66" y2="282" stroke="#c2410c" stroke-width="1.5" stroke-dasharray="2 2" />
        <line x1="228" y1="258" x2="228" y2="282" stroke="#c2410c" stroke-width="1.5" stroke-dasharray="2 2" />
        <rect class="badge-bg" x="122" y="267" width="50" height="22" rx="6" fill="#c2410c" />
        <text x="147" y="279" font-size="11.5" font-weight="700" fill="#ffffff" text-anchor="middle" dominant-baseline="central">Pace</text>
      </g>
    </svg>
  </div>

  
  <div class="units-list">
    <div class="unit-card active" data-unit="digit" style="--theme-color:#0369a1; --glow-color:rgba(3,105,161,0.15); --bg-light:#e0f2fe;">
      <div class="card-left">
        <span class="card-icon">☝️</span>
        <span class="card-title">Digit</span>
      </div>
      <span class="card-val">~0.75 in</span>
    </div>

    <div class="unit-card" data-unit="span" style="--theme-color:#0f766e; --glow-color:rgba(15,118,110,0.15); --bg-light:#ccfbf1;">
      <div class="card-left">
        <span class="card-icon">🖐️</span>
        <span class="card-title">Span</span>
      </div>
      <span class="card-val">~9 in</span>
    </div>

    <div class="unit-card" data-unit="cubit" style="--theme-color:#6d28d9; --glow-color:rgba(109,40,217,0.15); --bg-light:#ede9fe;">
      <div class="card-left">
        <span class="card-icon">💪</span>
        <span class="card-title">Cubit</span>
      </div>
      <span class="card-val">~18–20 in</span>
    </div>

    <div class="unit-card" data-unit="pace" style="--theme-color:#c2410c; --glow-color:rgba(194,65,12,0.15); --bg-light:#ffedd5;">
      <div class="card-left">
        <span class="card-icon">🚶</span>
        <span class="card-title">Pace</span>
      </div>
      <span class="card-val">~5 ft</span>
    </div>
  </div>
</div>

<script>
  const cards = document.querySelectorAll('.unit-card');
  const brackets = {
    digit: document.getElementById('br-digit'),
    span: document.getElementById('br-span'),
    cubit: document.getElementById('br-cubit'),
    pace: document.getElementById('br-pace')
  };

  function selectUnit(name) {
    cards.forEach(c => {
      const isMatch = c.getAttribute('data-unit') === name;
      c.classList.toggle('active', isMatch);
    });

    Object.keys(brackets).forEach(key => {
      if (brackets[key]) {
        brackets[key].classList.toggle('active', key === name);
      }
    });
  }

  // Interactive click handlers
  cards.forEach(card => {
    card.addEventListener('click', () => {
      clearInterval(autoTimer);
      selectUnit(card.getAttribute('data-unit'));
    });
  });

  // Auto-cycle through units smoothly
  let currentIndex = 0;
  const unitNames = ['digit', 'span', 'cubit', 'pace'];
  let autoTimer = setInterval(() => {
    currentIndex = (currentIndex + 1) % unitNames.length;
    selectUnit(unitNames[currentIndex]);
  }, 3200);

  // Pause auto-cycle on user interaction
  document.body.addEventListener('pointerdown', () => {
    clearInterval(autoTimer);
  });
</script>

</body>
</html>

<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <meta name="aspect-ratio" content="4:3">
  <style>
    * {
      box-sizing: border-box;
      margin: 0;
      padding: 0;
      user-select: none;
      -webkit-user-select: none;
    }

    body {
      font-family: system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
      color: #1e2945;
      background: transparent;
      padding: 10px;
      display: flex;
      flex-direction: column;
      justify-content: center;
      min-height: 100%;
    }

    .chart-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 10px;
      width: 100%;
      max-width: 620px;
      margin: 0 auto;
    }

    .piece-card {
      background: #ffffff;
      border: 2px solid #e2e8f0;
      border-radius: 12px;
      padding: 10px 6px;
      display: flex;
      flex-direction: column;
      align-items: center;
      text-align: center;
      cursor: pointer;
      transition: border-color 0.2s ease, box-shadow 0.2s ease, background-color 0.2s ease;
      position: relative;
    }

    .piece-card.active {
      border-color: #22b7ff;
      box-shadow: 0 4px 12px rgba(34, 183, 255, 0.2);
    }

    .piece-icon {
      font-size: 34px;
      line-height: 1;
      margin-bottom: 4px;
      filter: drop-shadow(0 2px 3px rgba(0, 0, 0, 0.12));
    }

    .piece-name {
      font-size: 13px;
      font-weight: 700;
      color: #475569;
      text-transform: uppercase;
      letter-spacing: 0.5px;
      margin-bottom: 4px;
    }

    .value-badge {
      display: inline-flex;
      align-items: center;
      justify-content: center;
      padding: 3px 10px;
      border-radius: 20px;
      font-size: 16px;
      font-weight: 800;
      margin-bottom: 6px;
      min-width: 50px;
    }

    .coins-box {
      display: flex;
      flex-wrap: wrap;
      justify-content: center;
      align-items: center;
      gap: 3px;
      min-height: 28px;
      padding: 2px;
      max-width: 80px;
    }

    .coin {
      width: 12px;
      height: 12px;
      background: #f59e0b;
      border: 1.5px solid #d97706;
      border-radius: 50%;
      box-shadow: 0 1px 2px rgba(0,0,0,0.15);
      display: inline-block;
    }

    .king-symbol {
      font-size: 18px;
      line-height: 1;
    }

    /* Card Themes */
    .theme-pawn .value-badge { background: #f1f5f9; color: #334155; }
    .theme-knight .value-badge { background: #e0f2fe; color: #0369a1; }
    .theme-bishop .value-badge { background: #ede9fe; color: #6d28d9; }
    .theme-rook .value-badge { background: #fef3c7; color: #b45309; }
    .theme-queen .value-badge { background: #ffe4e6; color: #be123c; }
    .theme-king .value-badge { background: #fef08a; color: #854d0e; font-size: 18px; }

    @media (max-width: 380px) {
      .chart-grid {
        grid-template-columns: repeat(2, 1fr);
        gap: 8px;
      }
      .piece-icon {
        font-size: 30px;
      }
      .value-badge {
        font-size: 14px;
        padding: 2px 8px;
      }
      .coin {
        width: 10px;
        height: 10px;
      }
    }
  </style>
</head>
<body>

  <div class="chart-grid" id="grid">
    
    <div class="piece-card theme-pawn active" onclick="selectPiece(this, 1)">
      <div class="piece-icon">♟</div>
      <div class="piece-name">Pawn</div>
      <div class="value-badge">1 pt</div>
      <div class="coins-box">
        <span class="coin"></span>
      </div>
    </div>

    
    <div class="piece-card theme-knight" onclick="selectPiece(this, 3)">
      <div class="piece-icon">♞</div>
      <div class="piece-name">Knight</div>
      <div class="value-badge">3 pts</div>
      <div class="coins-box">
        <span class="coin"></span>
        <span class="coin"></span>
        <span class="coin"></span>
      </div>
    </div>

    
    <div class="piece-card theme-bishop" onclick="selectPiece(this, 3)">
      <div class="piece-icon">♝</div>
      <div class="piece-name">Bishop</div>
      <div class="value-badge">3 pts</div>
      <div class="coins-box">
        <span class="coin"></span>
        <span class="coin"></span>
        <span class="coin"></span>
      </div>
    </div>

    
    <div class="piece-card theme-rook" onclick="selectPiece(this, 5)">
      <div class="piece-icon">♜</div>
      <div class="piece-name">Rook</div>
      <div class="value-badge">5 pts</div>
      <div class="coins-box">
        <span class="coin"></span>
        <span class="coin"></span>
        <span class="coin"></span>
        <span class="coin"></span>
        <span class="coin"></span>
      </div>
    </div>

    
    <div class="piece-card theme-queen" onclick="selectPiece(this, 9)">
      <div class="piece-icon">♛</div>
      <div class="piece-name">Queen</div>
      <div class="value-badge">9 pts</div>
      <div class="coins-box">
        <span class="coin"></span><span class="coin"></span><span class="coin"></span>
        <span class="coin"></span><span class="coin"></span><span class="coin"></span>
        <span class="coin"></span><span class="coin"></span><span class="coin"></span>
      </div>
    </div>

    
    <div class="piece-card theme-king" onclick="selectPiece(this, 99)">
      <div class="piece-icon">♚</div>
      <div class="piece-name">King</div>
      <div class="value-badge">∞</div >
      <div class="coins-box">
        <span class="king-symbol">👑</span>
      </div>
    </div>
  </div>

  <script>
    function playTone(freq, dur = 0.15) {
      try {
        const ctx = new (window.AudioContext || window.webkitAudioContext)();
        const osc = ctx.createOscillator();
        const gain = ctx.createGain();
        osc.frequency.value = freq;
        osc.connect(gain);
        gain.connect(ctx.destination);
        gain.gain.setValueAtTime(0.12, ctx.currentTime);
        gain.gain.exponentialRampToValueAtTime(0.001, ctx.currentTime + dur);
        osc.start();
        osc.stop(ctx.currentTime + dur);
      } catch (e) {}
    }

    function selectPiece(card, val) {
      document.querySelectorAll('.piece-card').forEach(c => c.classList.remove('active'));
      card.classList.add('active');
      const baseFreq = val === 99 ? 880 : 260 + (val * 55);
      playTone(baseFreq, 0.2);
    }
  </script>
</body>
</html>

Coordinate Grids and Piece Values in Chess Math

<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <meta name="aspect-ratio" content="4:3">
  <style>
    * { box-sizing: border-box; margin: 0; padding: 0; }
    body {
      font-family: system-ui, -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
      background: transparent;
      color: #1e2945;
      padding: 12px;
      display: flex;
      flex-direction: column;
      gap: 12px;
      min-height: 100%;
    }

    .grid {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 12px;
      width: 100%;
    }

    @media (max-width: 480px) {
      .grid {
        grid-template-columns: 1fr;
      }
    }

    .trade-card {
      background: #ffffff;
      border-radius: 12px;
      padding: 14px;
      display: flex;
      flex-direction: column;
      gap: 10px;
      border: 2px solid #e2e8f0;
      transition: box-shadow 0.2s ease;
    }

    .card-win {
      border-color: #86efac;
      background: linear-gradient(180deg, #f0fdf4 0%, #ffffff 60px);
    }

    .card-loss {
      border-color: #fca5a5;
      background: linear-gradient(180deg, #fef2f2 0%, #ffffff 60px);
    }

    .badge {
      align-self: flex-start;
      font-size: 11px;
      font-weight: 800;
      letter-spacing: 0.5px;
      padding: 4px 8px;
      border-radius: 6px;
      text-transform: uppercase;
    }

    .badge-win {
      background: #dcfce7;
      color: #15803d;
      border: 1px solid #bbf7d0;
    }

    .badge-loss {
      background: #fee2e2;
      color: #b91c1c;
      border: 1px solid #fecaca;
    }

    .steps {
      display: flex;
      flex-direction: column;
      gap: 8px;
    }

    .step-row {
      display: flex;
      align-items: center;
      justify-content: space-between;
      background: #f8fafc;
      border-radius: 8px;
      padding: 6px 10px;
      border: 1px solid #e2e8f0;
    }

    .piece-group {
      display: flex;
      align-items: center;
      gap: 6px;
    }

    .piece-icon {
      font-size: 26px;
      line-height: 1;
      filter: drop-shadow(0 1px 2px rgba(0,0,0,0.15));
    }

    .piece-val {
      font-size: 13px;
      font-weight: 700;
      padding: 2px 6px;
      border-radius: 4px;
    }

    .gain-val {
      background: #dcfce7;
      color: #166534;
    }

    .loss-val {
      background: #fee2e2;
      color: #991b1b;
    }

    .action-type {
      font-size: 12px;
      font-weight: 600;
      color: #64748b;
    }

    .math-box {
      border-radius: 8px;
      padding: 10px 12px;
      display: flex;
      align-items: center;
      justify-content: space-between;
      font-size: 15px;
      font-weight: 800;
      font-variant-numeric: tabular-nums;
      margin-top: auto;
    }

    .math-win {
      background: #15803d;
      color: #ffffff;
    }

    .math-loss {
      background: #b91c1c;
      color: #ffffff;
    }

    .net-tag {
      font-size: 13px;
      padding: 2px 8px;
      border-radius: 4px;
      background: rgba(255, 255, 255, 0.2);
    }
  </style>
</head>
<body>

  <div class="grid">
    
    <div class="trade-card card-win">
      <div class="badge badge-win">WINNING TRADE</div>
      
      <div class="steps">
        <div class="step-row">
          <span class="action-type">+ Gained</span>
          <div class="piece-group">
            <span class="piece-icon">♛</span>
            <span class="piece-val gain-val">+9</span>
          </div>
        </div>

        <div class="step-row">
          <span class="action-type">− Lost</span>
          <div class="piece-group">
            <span class="piece-icon">♖</span>
            <span class="piece-val loss-val">−5</span>
          </div>
        </div>
      </div>

      <div class="math-box math-win">
        <span>+9 − 5</span>
        <span class="net-tag">+4 Net</span>
      </div>
    </div>

    
    <div class="trade-card card-loss">
      <div class="badge badge-loss">LOSING TRADE</div>
      
      <div class="steps">
        <div class="step-row">
          <span class="action-type">+ Gained</span>
          <div class="piece-group">
            <span class="piece-icon">♜</span>
            <span class="piece-val gain-val">+5</span>
          </div>
        </div>

        <div class="step-row">
          <span class="action-type">− Lost</span>
          <div class="piece-group">
            <span class="piece-icon">♘</span>
            <span class="piece-icon">♗</span>
            <span class="piece-val loss-val">−6</span>
          </div>
        </div>
      </div>

      <div class="math-box math-loss">
        <span>+5 − 6</span>
        <span class="net-tag">−1 Net</span>
      </div>
    </div>
  </div>

</body>
</html>

<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <meta name="aspect-ratio" content="1:1">
  <style>
    * { box-sizing: border-box; margin: 0; padding: 0; }
    body {
      font-family: system-ui, -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
      background: #ffffff;
      color: #1e2945;
      display: flex;
      flex-direction: column;
      align-items: center;
      justify-content: center;
      padding: 12px;
      user-select: none;
    }

    .badges {
      display: flex;
      flex-wrap: wrap;
      justify-content: center;
      gap: 8px;
      margin-bottom: 8px;
      width: 100%;
      max-width: 420px;
    }

    .badge {
      font-size: 13px;
      font-weight: 700;
      padding: 5px 10px;
      border-radius: 6px;
      cursor: pointer;
      transition: opacity 0.2s ease, transform 0.1s ease;
      display: flex;
      align-items: center;
      gap: 6px;
      border: 1px solid transparent;
    }
    .badge-e4 {
      background: #e6f7ff;
      color: #0077b6;
      border-color: #22b7ff;
    }
    .badge-c7 {
      background: #fff0f0;
      color: #d93838;
      border-color: #ff6b6b;
    }
    .badge.dimmed {
      opacity: 0.4;
    }

    .board-container {
      width: 100%;
      max-width: 380px;
      aspect-ratio: 1 / 1;
      position: relative;
    }

    svg {
      width: 100%;
      height: 100%;
      display: block;
    }

    .square {
      cursor: pointer;
      transition: opacity 0.2s ease;
    }
    .square-light { fill: #f0f3f8; }
    .square-dark { fill: #d5deeb; }

    .axis-label {
      font-size: 11px;
      font-weight: 700;
      fill: #6b7280;
      text-anchor: middle;
      dominant-baseline: central;
      font-family: inherit;
    }
    .axis-active-e4 { fill: #0088cc; font-weight: 800; font-size: 12px; }
    .axis-active-c7 { fill: #d93838; font-weight: 800; font-size: 12px; }

    .crosshair-e4 {
      stroke: #22b7ff;
      stroke-width: 2.5;
      stroke-linecap: round;
      stroke-dasharray: 4 3;
    }
    .crosshair-c7 {
      stroke: #ff6b6b;
      stroke-width: 2.5;
      stroke-linecap: round;
      stroke-dasharray: 4 3;
    }

    .highlight-e4 {
      fill: #22b7ff;
      opacity: 0.85;
      stroke: #0088cc;
      stroke-width: 2;
      rx: 4px;
    }
    .highlight-c7 {
      fill: #ff6b6b;
      opacity: 0.85;
      stroke: #d93838;
      stroke-width: 2;
      rx: 4px;
    }

    .sq-text {
      font-size: 13px;
      font-weight: 800;
      fill: #ffffff;
      text-anchor: middle;
      dominant-baseline: central;
      pointer-events: none;
    }

    .hint {
      margin-top: 6px;
      font-size: 12px;
      color: #6b7280;
      text-align: center;
    }
  </style>
</head>
<body>

  <div class="badges">
    <div id="badgeE4" class="badge badge-e4" onclick="toggleSelection('e4')">
      <span>● e4</span>
      <span>= File e + Rank 4</span>
    </div>
    <div id="badgeC7" class="badge badge-c7" onclick="toggleSelection('c7')">
      <span>● c7</span>
      <span>= File c + Rank 7</span>
    </div>
  </div>

  <div class="board-container">
    <svg viewBox="0 0 360 360" id="chessSvg">
      
      
      <g id="gridSquares"></g>

      
      <g id="e4Group">
        
        <line x1="24" y1="196" x2="204" y2="196" class="crosshair-e4" />
        
        <line x1="204" y1="196" x2="204" y2="336" class="crosshair-e4" />
        
        <rect x="185" y="177" width="38" height="38" class="highlight-e4" />
        <text x="204" y="196" class="sq-text">e4</text>
      </g>

      <g id="c7Group">
        
        <line x1="24" y1="76" x2="124" y2="76" class="crosshair-c7" />
        
        <line x1="124" y1="76" x2="124" y2="336" class="crosshair-c7" />
        
        <rect x="105" y="57" width="38" height="38" class="highlight-c7" />
        <text x="124" y="76" class="sq-text">c7</text>
      </g>

      
      <g id="customGroup" style="display: none;">
        <line id="customCrossH" x1="24" y1="0" x2="0" y2="0" stroke="#8b5cf6" stroke-width="2.5" stroke-dasharray="4 3" />
        <line id="customCrossV" x1="0" y1="0" x2="0" y2="336" stroke="#8b5cf6" stroke-width="2.5" stroke-dasharray="4 3" />
        <rect id="customBox" x="0" y="0" width="38" height="38" fill="#8b5cf6" opacity="0.85" rx="4" stroke="#6d28d9" stroke-width="2" />
        <text id="customLabel" x="0" y="0" class="sq-text"></text>
      </g>

      
      <g id="rankLabels"></g>

      
      <g id="fileLabels"></g>
    </svg>
  </div>

  <div class="hint" id="hintText">Tap a square or badge to trace coordinates</div>

  <script>
    const files = ['a', 'b', 'c', 'd', 'e', 'f', 'g', 'h'];
    const ranks = ['8', '7', '6', '5', '4', '3', '2', '1']; // Top to bottom

    const originX = 24;
    const originY = 16;
    const sqSize = 40;

    let showE4 = true;
    let showC7 = true;

    // Draw board
    const gridG = document.getElementById('gridSquares');
    for (let r = 0; r < 8; r++) {
      for (let f = 0; f < 8; f++) {
        const rect = document.createElementNS('http://www.w3.org/2000/svg', 'rect');
        rect.setAttribute('x', originX + f * sqSize);
        rect.setAttribute('y', originY + r * sqSize);
        rect.setAttribute('width', sqSize);
        rect.setAttribute('height', sqSize);
        rect.setAttribute('class', `square ${(r + f) % 2 === 0 ? 'square-light' : 'square-dark'}`);
        
        const fileChar = files[f];
        const rankNum = ranks[r];
        rect.setAttribute('data-sq', fileChar + rankNum);
        rect.onclick = () => selectCustomSquare(f, r, fileChar, rankNum);
        gridG.appendChild(rect);
      }
    }

    // Rank labels
    const rankG = document.getElementById('rankLabels');
    ranks.forEach((rnk, i) => {
      const txt = document.createElementNS('http://www.w3.org/2000/svg', 'text');
      txt.setAttribute('x', 12);
      txt.setAttribute('y', originY + i * sqSize + sqSize / 2);
      txt.setAttribute('id', 'rank-lbl-' + rnk);
      txt.setAttribute('class', `axis-label ${rnk === '4' ? 'axis-active-e4' : rnk === '7' ? 'axis-active-c7' : ''}`);
      txt.textContent = rnk;
      rankG.appendChild(txt);
    });

    // File labels
    const fileG = document.getElementById('fileLabels');
    files.forEach((fil, i) => {
      const txt = document.createElementNS('http://www.w3.org/2000/svg', 'text');
      txt.setAttribute('x', originX + i * sqSize + sqSize / 2);
      txt.setAttribute('y', originY + 8 * sqSize + 14);
      txt.setAttribute('id', 'file-lbl-' + fil);
      txt.setAttribute('class', `axis-label ${fil === 'e' ? 'axis-active-e4' : fil === 'c' ? 'axis-active-c7' : ''}`);
      txt.textContent = fil;
      fileG.appendChild(txt);
    });

    function toggleSelection(type) {
      if (type === 'e4') {
        showE4 = !showE4;
      } else if (type === 'c7') {
        showC7 = !showC7;
      }
      
      // Clear custom when clicking badges
      document.getElementById('customGroup').style.display = 'none';

      document.getElementById('e4Group').style.display = showE4 ? 'inline' : 'none';
      document.getElementById('c7Group').style.display = showC7 ? 'inline' : 'none';
      
      document.getElementById('badgeE4').classList.toggle('dimmed', !showE4);
      document.getElementById('badgeC7').classList.toggle('dimmed', !showC7);

      updateAxisHighlights();
    }

    function selectCustomSquare(fIdx, rIdx, fileChar, rankNum) {
      const cx = originX + fIdx * sqSize + sqSize / 2;
      const cy = originY + rIdx * sqSize + sqSize / 2;
      
      const customG = document.getElementById('customGroup');
      customG.style.display = 'inline';

      const cH = document.getElementById('customCrossH');
      cH.setAttribute('x1', originX);
      cH.setAttribute('y1', cy);
      cH.setAttribute('x2', cx);
      cH.setAttribute('y2', cy);

      const cV = document.getElementById('customCrossV');
      cV.setAttribute('x1', cx);
      cV.setAttribute('y1', cy);
      cV.setAttribute('x2', cx);
      cV.setAttribute('y2', originY + 8 * sqSize);

      const box = document.getElementById('customBox');
      box.setAttribute('x', originX + fIdx * sqSize + 1);
      box.setAttribute('y', originY + rIdx * sqSize + 1);

      const lbl = document.getElementById('customLabel');
      lbl.setAttribute('x', cx);
      lbl.setAttribute('y', cy);
      lbl.textContent = fileChar + rankNum;

      document.getElementById('hintText').innerHTML = `Selected: <b>${fileChar}${rankNum}</b> = File ${fileChar} + Rank ${rankNum}`;
    }

    function updateAxisHighlights() {
      const eRank = document.getElementById('rank-lbl-4');
      const eFile = document.getElementById('file-lbl-e');
      const cRank = document.getElementById('rank-lbl-7');
      const cFile = document.getElementById('file-lbl-c');

      eRank.className.baseVal = `axis-label ${showE4 ? 'axis-active-e4' : ''}`;
      eFile.className.baseVal = `axis-label ${showE4 ? 'axis-active-e4' : ''}`;
      cRank.className.baseVal = `axis-label ${showC7 ? 'axis-active-c7' : ''}`;
      cFile.className.baseVal = `axis-label ${showC7 ? 'axis-active-c7' : ''}`;
    }
  </script>
</body>
</html>

OGM.4.PR.2

Aligned learning resources

Related diagrams