<!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">
  <title>Bounding Square Roots</title>
  <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: #ffffff;
      display: flex;
      flex-direction: column;
      align-items: center;
      justify-content: space-between;
      min-height: 100%;
      padding: 16px 12px;
      user-select: none;
    }

    .stepper-nav {
      display: flex;
      gap: 8px;
      margin-bottom: 12px;
      width: 100%;
      max-width: 520px;
    }
    .step-btn {
      flex: 1;
      padding: 8px 10px;
      font-size: 13px;
      font-weight: 700;
      color: #64748b;
      background: #f1f5f9;
      border: 1px solid #e2e8f0;
      border-radius: 8px;
      cursor: pointer;
      text-align: center;
      transition: all 0.25s ease;
    }
    .step-btn.active {
      color: #1e2945;
      background: #eff6ff;
      border-color: #3b82f6;
      box-shadow: 0 0 0 1px #3b82f6;
    }

    .callout-box {
      width: 100%;
      max-width: 520px;
      min-height: 52px;
      display: flex;
      align-items: center;
      justify-content: center;
      background: #f8fafc;
      border: 1px solid #e2e8f0;
      border-radius: 10px;
      margin-bottom: 8px;
      padding: 8px 16px;
      text-align: center;
    }
    .callout-text {
      font-size: 16px;
      font-weight: 700;
      letter-spacing: -0.2px;
    }
    .rad-tag {
      color: #059669;
      background: #ecfdf5;
      padding: 2px 6px;
      border-radius: 6px;
      border: 1px solid #a7f3d0;
    }
    .int-tag {
      color: #2563eb;
      background: #eff6ff;
      padding: 2px 6px;
      border-radius: 6px;
      border: 1px solid #bfdbfe;
    }

    .svg-wrapper {
      width: 100%;
      max-width: 560px;
      flex: 1;
      display: flex;
      align-items: center;
      justify-content: center;
    }
    svg {
      width: 100%;
      height: auto;
      overflow: visible;
    }

    /* Interactive / Animated SVG Elements */
    .bracket-zone {
      transition: opacity 0.4s ease;
    }
    .glow-pin {
      transition: transform 0.4s ease, filter 0.4s ease;
    }
    .highlight-glow {
      filter: drop-shadow(0 0 6px rgba(16, 185, 129, 0.6));
    }
    .active-val {
      font-weight: 800;
    }
  </style>
</head>
<body>

  
  <div class="stepper-nav">
    <button class="step-btn active" id="btn1" onclick="setStep(1)">Step 1: Bracket Radicand</button>
    <button class="step-btn" id="btn2" onclick="setStep(2)">Step 2: Simplify Roots</button>
  </div>

  
  <div class="callout-box">
    <div id="callout" class="callout-text">
      <span class="rad-tag">64</span> &lt; <span class="rad-tag" style="background:#d1fae5; border-color:#34d399; font-size:1.1em;">75</span> &lt; <span class="rad-tag">81</span>
    </div>
  </div>

  
  <div class="svg-wrapper">
    <svg viewBox="0 0 560 210" aria-label="Square root number line">
      <defs>
        
        <linearGradient id="rangeGrad" x1="0%" y1="0%" x2="100%" y2="0%">
          <stop offset="0%" stop-color="#3b82f6" stop-opacity="0.15" />
          <stop offset="100%" stop-color="#10b981" stop-opacity="0.15" />
        </linearGradient>
        <filter id="emeraldGlow" x="-20%" y="-20%" width="140%" height="140%">
          <feGaussianBlur stdDeviation="3" result="blur" />
          <feComposite in="SourceGraphic" in2="blur" operator="over" />
        </filter>
      </defs>

      
      <rect id="boundRect" x="206.7" y="55" width="166.6" height="50" rx="8" fill="url(#rangeGrad)" stroke="#3b82f6" stroke-dasharray="4 3" stroke-width="1.5" />

      
      <g id="distGroup" opacity="1" style="transition: opacity 0.3s ease;">
        <path d="M 216.7 50 Q 263.3 28 310 48" fill="none" stroke="#64748b" stroke-width="1.5" stroke-dasharray="3 3"/>
        <text x="260" y="32" font-size="11" fill="#64748b" font-weight="700" text-anchor="middle">+11</text>

        <path d="M 314 48 Q 343 32 373.3 50" fill="none" stroke="#059669" stroke-width="1.5" stroke-dasharray="3 3"/>
        <text x="345" y="32" font-size="11" fill="#059669" font-weight="700" text-anchor="middle">-6 (closer!)</text>
      </g>

      
      <line x1="40" y1="80" x2="520" y2="80" stroke="#cbd5e1" stroke-width="3" stroke-linecap="round" />

      
      <path d="M 38 75 L 30 80 L 38 85" fill="none" stroke="#94a3b8" stroke-width="2.5" stroke-linecap="round" stroke-linejoin="round"/>
      <path d="M 522 75 L 530 80 L 522 85" fill="none" stroke="#94a3b8" stroke-width="2.5" stroke-linecap="round" stroke-linejoin="round"/>

      
      
      <g transform="translate(50, 0)">
        <line y1="72" y2="88" stroke="#94a3b8" stroke-width="2" stroke-linecap="round" />
        <text y="64" font-size="17" fill="#64748b" font-weight="600" text-anchor="middle">7</text>
        <text y="112" font-size="15" fill="#94a3b8" font-weight="600" text-anchor="middle">√49</text>
      </g>

      
      <g transform="translate(216.7, 0)">
        <line y1="68" y2="92" stroke="#2563eb" stroke-width="3" stroke-linecap="round" />
        <text id="int8" y="64" font-size="19" fill="#2563eb" font-weight="800" text-anchor="middle">8</text>
        <text id="rad64" y="114" font-size="17" fill="#2563eb" font-weight="800" text-anchor="middle">√64</text>
      </g>

      
      <g transform="translate(383.3, 0)">
        <line y1="68" y2="92" stroke="#2563eb" stroke-width="3" stroke-linecap="round" />
        <text id="int9" y="64" font-size="19" fill="#2563eb" font-weight="800" text-anchor="middle">9</text>
        <text id="rad81" y="114" font-size="17" fill="#2563eb" font-weight="800" text-anchor="middle">√81</text>
      </g>

      
      <g transform="translate(510, 0)">
        <line y1="72" y2="88" stroke="#94a3b8" stroke-width="2" stroke-linecap="round" />
        <text y="64" font-size="17" fill="#64748b" font-weight="600" text-anchor="middle">10</text>
        <text y="112" font-size="15" fill="#94a3b8" font-weight="600" text-anchor="middle">√100</text>
      </g>

      
      <g id="pinGroup" class="glow-pin highlight-glow" transform="translate(326.7, 0)">
        
        <line y1="56" y2="104" stroke="#059669" stroke-width="2.5" stroke-dasharray="2 2" />
        
        
        <circle cy="80" r="7" fill="#10b981" stroke="#ffffff" stroke-width="2.5" />

        
        <g transform="translate(0, 150)">
          <rect x="-34" y="-20" width="68" height="34" rx="8" fill="#059669" filter="url(#emeraldGlow)" />
          <polygon points="-6,-20 6,-20 0,-27" fill="#059669" />
          <text y="3" font-size="16" fill="#ffffff" font-weight="800" text-anchor="middle">√75</text>
          <text y="28" font-size="12" fill="#059669" font-weight="700" text-anchor="middle">≈ 8.66</text>
        </g>
      </g>
    </svg>
  </div>

  <script>
    function setStep(step) {
      const b1 = document.getElementById('btn1');
      const b2 = document.getElementById('btn2');
      const callout = document.getElementById('callout');
      const distGroup = document.getElementById('distGroup');
      const rad64 = document.getElementById('rad64');
      const rad81 = document.getElementById('rad81');
      const int8 = document.getElementById('int8');
      const int9 = document.getElementById('int9');
      const boundRect = document.getElementById('boundRect');

      if (step === 1) {
        b1.classList.add('active');
        b2.classList.remove('active');
        callout.innerHTML = '<span class="rad-tag">64</span> &lt; <span class="rad-tag" style="background:#d1fae5; border-color:#34d399; font-size:1.08em;">75</span> &lt; <span class="rad-tag">81</span>';
        distGroup.setAttribute('opacity', '1');
        
        rad64.setAttribute('fill', '#059669');
        rad81.setAttribute('fill', '#059669');
        int8.setAttribute('fill', '#64748b');
        int9.setAttribute('fill', '#64748b');
        boundRect.setAttribute('stroke', '#10b981');
      } else {
        b2.classList.add('active');
        b1.classList.remove('active');
        callout.innerHTML = '<span class="int-tag">8</span> &lt; <span class="rad-tag" style="background:#d1fae5; border-color:#34d399; font-size:1.08em;">√75</span> &lt; <span class="int-tag">9</span>';
        distGroup.setAttribute('opacity', '0.2');

        rad64.setAttribute('fill', '#64748b');
        rad81.setAttribute('fill', '#64748b');
        int8.setAttribute('fill', '#2563eb');
        int9.setAttribute('fill', '#2563eb');
        boundRect.setAttribute('stroke', '#3b82f6');
      }
    }

    // Initialize with Step 1
    setStep(1);
  </script>
</body>
</html>

Bounding Square Roots Between Consecutive Integers

<!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 {
      background-color: #f8f9fa;
      color: #1e2945;
      font-family: system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
      display: flex;
      flex-direction: column;
      align-items: center;
      justify-content: center;
      min-height: 100%;
      padding: 16px 8px;
    }

    .squares-container {
      display: flex;
      align-items: flex-end;
      justify-content: center;
      gap: 16px;
      width: 100%;
      max-width: 480px;
      margin-bottom: 22px;
    }

    .square-col {
      display: flex;
      flex-direction: column;
      align-items: center;
      flex: 1;
    }

    .side-top-label {
      font-size: 14px;
      font-weight: 700;
      margin-bottom: 6px;
      height: 20px;
      display: flex;
      align-items: center;
      justify-content: center;
    }

    .square-row {
      display: flex;
      align-items: center;
      justify-content: center;
      width: 100%;
    }

    .side-left-label {
      font-size: 14px;
      font-weight: 700;
      margin-right: 6px;
      width: 16px;
      text-align: right;
    }

    .geo-square {
      border-radius: 8px;
      display: flex;
      flex-direction: column;
      align-items: center;
      justify-content: center;
      transition: box-shadow 0.2s ease, transform 0.2s ease;
      cursor: pointer;
    }

    /* Proportional geometric dimensions */
    .sq-49 {
      width: 77px;
      height: 77px;
      background: #eff6ff;
      border: 2px solid #3b82f6;
      color: #1d4ed8;
    }

    .sq-50 {
      width: 77.8px;
      height: 77.8px;
      background: #fffbeb;
      border: 2px dashed #f59e0b;
      color: #b45309;
    }

    .sq-64 {
      width: 88px;
      height: 88px;
      background: #f0fdf4;
      border: 2px solid #22c55e;
      color: #15803d;
    }

    .geo-square:hover, .geo-square.active {
      box-shadow: 0 4px 12px rgba(0, 0, 0, 0.08);
    }

    .area-text {
      font-size: 13px;
      font-weight: 700;
      line-height: 1.2;
      text-align: center;
    }

    .inequality-card {
      background: #ffffff;
      border: 1px solid #e6e6e6;
      border-radius: 12px;
      padding: 14px 20px;
      display: flex;
      flex-direction: column;
      align-items: center;
      gap: 8px;
      width: fit-content;
      max-width: 90%;
      box-shadow: 0 1px 3px rgba(0,0,0,0.02);
    }

    .inequality-row {
      display: flex;
      align-items: center;
      justify-content: center;
      gap: 10px;
      font-size: 17px;
      font-weight: 700;
      letter-spacing: -0.01em;
    }

    .tag-blue { color: #1d4ed8; }
    .tag-orange { color: #b45309; }
    .tag-green { color: #15803d; }
    .operator { color: #94a3b8; font-weight: 600; }

    .arrow-down {
      font-size: 13px;
      color: #64748b;
      display: flex;
      align-items: center;
      gap: 4px;
      font-weight: 600;
    }

    @media (max-width: 380px) {
      .squares-container {
        gap: 8px;
      }
      .sq-49 {
        width: 68px;
        height: 68px;
      }
      .sq-50 {
        width: 68.7px;
        height: 68.7px;
      }
      .sq-64 {
        width: 78px;
        height: 78px;
      }
      .area-text {
        font-size: 12px;
      }
      .side-top-label, .side-left-label {
        font-size: 13px;
      }
      .inequality-row {
        font-size: 15px;
      }
    }
  </style>
</head>
<body>

  <div class="squares-container">
    
    <div class="square-col">
      <div class="side-top-label tag-blue">7</div>
      <div class="square-row">
        <div class="side-left-label tag-blue">7</div>
        <div class="geo-square sq-49">
          <div class="area-text">Area<br>49</div>
        </div>
      </div>
    </div>

    
    <div class="square-col">
      <div class="side-top-label tag-orange">√50</div>
      <div class="square-row">
        <div class="side-left-label tag-orange">?</div>
        <div class="geo-square sq-50">
          <div class="area-text">Area<br>50</div>
        </div>
      </div>
    </div>

    
    <div class="square-col">
      <div class="side-top-label tag-green">8</div>
      <div class="square-row">
        <div class="side-left-label tag-green">8</div>
        <div class="geo-square sq-64">
          <div class="area-text">Area<br>64</div>
        </div>
      </div>
    </div>
  </div>

  
  <div class="inequality-card">
    <div class="inequality-row">
      <span class="tag-blue">49</span>
      <span class="operator">&lt;</span>
      <span class="tag-orange">50</span>
      <span class="operator">&lt;</span>
      <span class="tag-green">64</span>
    </div>
    
    <div class="arrow-down">
      <span>↓</span>
      <span>√</span>
    </div>

    <div class="inequality-row">
      <span class="tag-blue">7</span>
      <span class="operator">&lt;</span>
      <span class="tag-orange">√50</span>
      <span class="operator">&lt;</span>
      <span class="tag-green">8</span>
    </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, sans-serif;
      color: #1e2945;
      background: #ffffff;
      padding: 12px;
      display: flex;
      flex-direction: column;
      align-items: center;
      justify-content: space-between;
      min-height: 100%;
    }

    .header-bar {
      display: flex;
      align-items: center;
      justify-content: space-between;
      width: 100%;
      max-width: 520px;
      margin-bottom: 8px;
    }

    .title-tag {
      font-size: 13px;
      font-weight: 700;
      text-transform: uppercase;
      letter-spacing: 0.5px;
      color: #64748b;
    }

    .preview-box {
      font-size: 15px;
      font-weight: 700;
      color: #0284c7;
      background: #f0f9ff;
      border: 1px solid #bae6fd;
      padding: 4px 10px;
      border-radius: 8px;
    }

    /* Grid of 12 numbers */
    .grid-container {
      display: grid;
      grid-template-columns: repeat(6, 1fr);
      gap: 6px;
      width: 100%;
      max-width: 520px;
    }

    .num-pair {
      background: #f8fafc;
      border: 1px solid #e2e8f0;
      border-radius: 8px;
      padding: 6px 2px;
      display: flex;
      flex-direction: column;
      align-items: center;
      gap: 2px;
      transition: background 0.25s, border-color 0.25s, box-shadow 0.25s;
      cursor: pointer;
      user-select: none;
    }

    .top-val {
      font-size: 15px;
      font-weight: 700;
      color: #334155;
    }

    .arrow-icon {
      font-size: 11px;
      color: #94a3b8;
      line-height: 1;
    }

    .bot-val {
      font-size: 14px;
      font-weight: 800;
      color: #0369a1;
    }

    /* Bound Highlights */
    .num-pair.bound-left {
      background: #eff6ff;
      border-color: #3b82f6;
      box-shadow: 0 0 0 2px #3b82f6;
    }
    .num-pair.bound-right {
      background: #eff6ff;
      border-color: #3b82f6;
      box-shadow: 0 0 0 2px #3b82f6;
    }
    .num-pair.bound-exact {
      background: #ecfdf5;
      border-color: #10b981;
      box-shadow: 0 0 0 2px #10b981;
    }

    /* Interactive Bound Explorer */
    .bounds-control {
      width: 100%;
      max-width: 520px;
      background: #f8fafc;
      border: 1px solid #e2e8f0;
      border-radius: 12px;
      padding: 10px 14px;
      display: flex;
      flex-direction: column;
      gap: 8px;
      margin-top: 8px;
    }

    .slider-row {
      display: flex;
      align-items: center;
      gap: 12px;
    }

    .slider-label {
      font-size: 13px;
      font-weight: 700;
      white-space: nowrap;
      color: #475569;
    }

    input[type="range"] {
      flex: 1;
      accent-color: #0284c7;
      cursor: pointer;
      height: 6px;
    }

    .bound-math {
      display: flex;
      align-items: center;
      justify-content: center;
      gap: 8px;
      font-size: 17px;
      font-weight: 800;
      padding: 6px 0 2px;
    }

    .tag-int {
      color: #334155;
      background: #e2e8f0;
      padding: 2px 8px;
      border-radius: 6px;
    }

    .tag-root {
      color: #0284c7;
      background: #e0f2fe;
      padding: 2px 10px;
      border-radius: 6px;
    }

    .quick-chips {
      display: flex;
      justify-content: center;
      gap: 6px;
      flex-wrap: wrap;
    }

    .chip-btn {
      background: #ffffff;
      border: 1px solid #cbd5e1;
      color: #334155;
      font-size: 12px;
      font-weight: 700;
      padding: 4px 10px;
      border-radius: 16px;
      cursor: pointer;
      transition: all 0.15s;
    }
    .chip-btn.active {
      background: #0284c7;
      border-color: #0284c7;
      color: #ffffff;
    }

    @media (max-width: 400px) {
      .grid-container {
        grid-template-columns: repeat(4, 1fr);
        gap: 5px;
      }
      .top-val { font-size: 14px; }
      .bot-val { font-size: 13px; }
      .bound-math { font-size: 15px; }
    }
  </style>
</head>
<body>

  <div class="header-bar">
    <span class="title-tag">x → x² (Perfect Squares)</span>
    <span id="previewTag" class="preview-box">√50 ≈ 7.07</span>
  </div>

  <div class="grid-container" id="grid">
    
  </div>

  <div class="bounds-control">
    <div class="slider-row">
      <span class="slider-label">Radicand:</span>
      <input type="range" id="radicandSlider" min="1" max="144" value="50">
    </div>

    <div class="bound-math" id="boundOutput">
      
    </div>

    <div class="quick-chips">
      <button class="chip-btn" data-val="20">√20</button>
      <button class="chip-btn active" data-val="50">√50</button>
      <button class="chip-btn" data-val="75">√75</button>
      <button class="chip-btn" data-val="110">√110</button>
    </div>
  </div>

  <script>
    const squares = [
      { x: 1, sq: 1 },
      { x: 2, sq: 4 },
      { x: 3, sq: 9 },
      { x: 4, sq: 16 },
      { x: 5, sq: 25 },
      { x: 6, sq: 36 },
      { x: 7, sq: 49 },
      { x: 8, sq: 64 },
      { x: 9, sq: 81 },
      { x: 10, sq: 100 },
      { x: 11, sq: 121 },
      { x: 12, sq: 144 }
    ];

    const grid = document.getElementById('grid');
    const slider = document.getElementById('radicandSlider');
    const boundOutput = document.getElementById('boundOutput');
    const previewTag = document.getElementById('previewTag');
    const chipBtns = document.querySelectorAll('.chip-btn');

    // Build grid cells
    squares.forEach(item => {
      const card = document.createElement('div');
      card.className = 'num-pair';
      card.id = `pair-${item.x}`;
      card.innerHTML = `
        <span class="top-val">${item.x}</span>
        <span class="arrow-icon">↓ x²</span>
        <span class="bot-val">${item.sq}</span>
      `;
      card.onclick = () => updateRadicand(item.sq);
      grid.appendChild(card);
    });

    function updateRadicand(n) {
      slider.value = n;
      const root = Math.sqrt(n);
      previewTag.textContent = Number.isInteger(root) ? `√${n} = ${root}` : `√${n} ≈ ${root.toFixed(2)}`;

      // Reset card highlights
      document.querySelectorAll('.num-pair').forEach(p => {
        p.className = 'num-pair';
      });

      // Update chips active state
      chipBtns.forEach(btn => {
        btn.classList.toggle('active', parseInt(btn.dataset.val) === n);
      });

      // Find bounding squares
      let exact = null;
      let left = null;
      let right = null;

      for (let i = 0; i < squares.length; i++) {
        if (squares[i].sq === n) {
          exact = squares[i];
          break;
        }
        if (squares[i].sq < n) {
          left = squares[i];
        }
        if (squares[i].sq > n && right === null) {
          right = squares[i];
        }
      }

      if (exact) {
        document.getElementById(`pair-${exact.x}`).classList.add('bound-exact');
        boundOutput.innerHTML = `
          <span class="tag-root">√${n}</span>
          <span>=</span>
          <span class="tag-int">${exact.x}</span>
        `;
      } else if (left && right) {
        document.getElementById(`pair-${left.x}`).classList.add('bound-left');
        document.getElementById(`pair-${right.x}`).classList.add('bound-right');
        boundOutput.innerHTML = `
          <span class="tag-int">${left.x}</span>
          <span>&lt;</span>
          <span class="tag-root">√${n}</span>
          <span>&lt;</span>
          <span class="tag-int">${right.x}</span>
        `;
      } else if (!left && right) {
        document.getElementById(`pair-${right.x}`).classList.add('bound-right');
        boundOutput.innerHTML = `
          <span class="tag-root">√${n}</span>
          <span>&lt;</span>
          <span class="tag-int">${right.x}</span>
        `;
      } else if (left && !right) {
        document.getElementById(`pair-${left.x}`).classList.add('bound-left');
        boundOutput.innerHTML = `
          <span class="tag-int">${left.x}</span>
          <span>&lt;</span>
          <span class="tag-root">√${n}</span>
        `;
      }
    }

    slider.addEventListener('input', (e) => {
      updateRadicand(parseInt(e.target.value));
    });

    chipBtns.forEach(btn => {
      btn.addEventListener('click', () => {
        updateRadicand(parseInt(btn.dataset.val));
      });
    });

    // Initial state: 50
    updateRadicand(50);
  </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; }
    body {
      font-family: system-ui, -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
      background: #ffffff;
      color: #1e2945;
      padding: 12px;
      display: flex;
      flex-direction: column;
      align-items: center;
      justify-content: space-between;
      min-height: 100%;
      user-select: none;
      -webkit-user-select: none;
    }

    /* Top interactive badges */
    .badges-row {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 8px;
      width: 100%;
      max-width: 520px;
    }

    .badge-card {
      background: #f8fafc;
      border: 2px solid #e2e8f0;
      border-radius: 10px;
      padding: 8px 6px;
      text-align: center;
      cursor: pointer;
      transition: all 0.25s ease;
    }

    .badge-card:hover {
      background: #f1f5f9;
    }

    .badge-card .tag-name {
      font-size: 13px;
      font-weight: 700;
      line-height: 1.2;
    }

    .badge-card .tag-val {
      font-size: 11px;
      margin-top: 2px;
      font-weight: 600;
      opacity: 0.8;
    }

    /* Card color identities */
    .badge-radical { color: #0284c7; }
    .badge-radicand { color: #059669; }
    .badge-root { color: #7c3aed; }

    /* Main Equation Anatomy Stage */
    .stage {
      position: relative;
      background: #f8fafc;
      border: 2px solid #e2e8f0;
      border-radius: 14px;
      width: 100%;
      max-width: 520px;
      padding: 20px 12px 14px;
      display: flex;
      flex-direction: column;
      align-items: center;
      justify-content: center;
      transition: border-color 0.25s ease;
    }

    .equation-display {
      display: flex;
      align-items: baseline;
      justify-content: center;
      font-size: 44px;
      font-weight: 700;
      letter-spacing: -0.5px;
      cursor: pointer;
    }

    .radical-group {
      display: inline-flex;
      align-items: baseline;
      position: relative;
    }

    .sym-radical {
      color: #0284c7;
      font-family: serif;
      font-size: 52px;
      line-height: 1;
      transform: translateY(2px);
      padding: 2px 4px 2px 6px;
      border-radius: 6px;
      transition: all 0.25s ease;
    }

    .radicand-box {
      color: #059669;
      border-top: 3.5px solid #0284c7;
      padding: 2px 6px 0 2px;
      border-radius: 0 4px 6px 0;
      margin-left: -2px;
      transition: all 0.25s ease;
    }

    .sym-eq {
      color: #64748b;
      margin: 0 10px;
      font-size: 36px;
    }

    .root-val {
      color: #7c3aed;
      padding: 2px 8px;
      border-radius: 6px;
      transition: all 0.25s ease;
    }

    /* Active Highlight States */
    .active-radical .sym-radical,
    .badge-card.active-radical {
      background: #e0f2fe;
      box-shadow: 0 0 0 2px #0284c7;
      border-color: #0284c7;
    }

    .active-radicand .radicand-box,
    .badge-card.active-radicand {
      background: #dcfce7;
      box-shadow: 0 0 0 2px #059669;
      border-color: #059669;
    }

    .active-root .root-val,
    .badge-card.active-root {
      background: #f3e8ff;
      box-shadow: 0 0 0 2px #7c3aed;
      border-color: #7c3aed;
    }

    /* Dimming inactive parts */
    .dimmed {
      opacity: 0.25;
    }

    /* Bottom Relationship Panel */
    .rel-panel {
      width: 100%;
      max-width: 520px;
      background: #ffffff;
      border: 1.5px solid #e2e8f0;
      border-radius: 12px;
      padding: 10px 12px;
      display: flex;
      align-items: center;
      justify-content: space-between;
      gap: 6px;
    }

    .rel-pill {
      flex: 1;
      background: #f8fafc;
      border: 1.5px solid #e2e8f0;
      border-radius: 8px;
      padding: 8px 4px;
      text-align: center;
      cursor: pointer;
      font-size: 13px;
      font-weight: 700;
      color: #1e2945;
      transition: all 0.25s ease;
    }

    .rel-pill:hover {
      background: #f1f5f9;
    }

    .rel-pill.active {
      background: #eff6ff;
      border-color: #0284c7;
      box-shadow: 0 0 0 1px #0284c7;
    }

    .rel-arrow {
      display: flex;
      flex-direction: column;
      align-items: center;
      justify-content: center;
      padding: 0 4px;
      color: #64748b;
      font-size: 11px;
      font-weight: 600;
      text-transform: uppercase;
      letter-spacing: 0.5px;
    }

    .arrow-icon {
      font-size: 16px;
      line-height: 1;
      color: #0284c7;
      margin-top: 2px;
    }

    /* Reset button */
    .reset-btn {
      align-self: center;
      font-size: 12px;
      font-weight: 600;
      color: #64748b;
      background: transparent;
      border: none;
      cursor: pointer;
      padding: 4px 8px;
      border-radius: 4px;
      transition: color 0.2s;
    }

    .reset-btn:hover {
      color: #1e2945;
      text-decoration: underline;
    }
  </style>
</head>
<body>

  
  <div class="badges-row">
    <div class="badge-card badge-radical" id="badgeRadical" onclick="selectPart('radical')">
      <div class="tag-name">Radical</div>
      <div class="tag-val">Symbol √</div>
    </div>
    <div class="badge-card badge-radicand" id="badgeRadicand" onclick="selectPart('radicand')">
      <div class="tag-name">Radicand</div>
      <div class="tag-val">Inside 144</div>
    </div>
    <div class="badge-card badge-root" id="badgeRoot" onclick="selectPart('root')">
      <div class="tag-name">Square Root</div>
      <div class="tag-val">Result 12</div>
    </div>
  </div>

  
  <div class="stage" id="stage">
    <div class="equation-display">
      <div class="radical-group">
        <span class="sym-radical" id="eqRadical" onclick="selectPart('radical')">√</span>
        <span class="radicand-box" id="eqRadicand" onclick="selectPart('radicand')">144</span>
      </div>
      <span class="sym-eq">=</span>
      <span class="root-val" id="eqRoot" onclick="selectPart('root')">12</span>
    </div>
  </div>

  
  <div class="rel-panel">
    <div class="rel-pill" id="pillSquare" onclick="selectPart('square-rel')">
      12² = 144<br><span style="font-size:11px;font-weight:500;color:#64748b;">Squaring</span>
    </div>
    <div class="rel-arrow">
      <span>Inverse</span>
      <span class="arrow-icon">⇄</span>
    </div>
    <div class="rel-pill" id="pillRoot" onclick="selectPart('root-rel')">
      √144 = 12<br><span style="font-size:11px;font-weight:500;color:#64748b;">Square Root</span>
    </div>
  </div>

  
  <button class="reset-btn" onclick="resetAll()">↺ Show All Parts</button>

  <script>
    let activeKey = null;

    const els = {
      badgeRadical: document.getElementById('badgeRadical'),
      badgeRadicand: document.getElementById('badgeRadicand'),
      badgeRoot: document.getElementById('badgeRoot'),
      eqRadical: document.getElementById('eqRadical'),
      eqRadicand: document.getElementById('eqRadicand'),
      eqRoot: document.getElementById('eqRoot'),
      pillSquare: document.getElementById('pillSquare'),
      pillRoot: document.getElementById('pillRoot')
    };

    function resetAll() {
      activeKey = null;
      document.querySelectorAll('.active-radical, .active-radicand, .active-root, .active').forEach(el => {
        el.classList.remove('active-radical', 'active-radicand', 'active-root', 'active');
      });
      document.querySelectorAll('.dimmed').forEach(el => el.classList.remove('dimmed'));
    }

    function selectPart(key) {
      if (activeKey === key) {
        resetAll();
        return;
      }
      resetAll();
      activeKey = key;

      const allInteractive = [
        els.badgeRadical, els.badgeRadicand, els.badgeRoot,
        els.eqRadical, els.eqRadicand, els.eqRoot,
        els.pillSquare, els.pillRoot
      ];

      allInteractive.forEach(el => el.classList.add('dimmed'));

      if (key === 'radical') {
        els.badgeRadical.classList.remove('dimmed');
        els.badgeRadical.classList.add('active-radical');
        els.eqRadical.classList.remove('dimmed');
        els.eqRadical.classList.add('active-radical');
        els.pillRoot.classList.remove('dimmed');
      } else if (key === 'radicand') {
        els.badgeRadicand.classList.remove('dimmed');
        els.badgeRadicand.classList.add('active-radicand');
        els.eqRadicand.classList.remove('dimmed');
        els.eqRadicand.classList.add('active-radicand');
        els.pillSquare.classList.remove('dimmed');
        els.pillRoot.classList.remove('dimmed');
      } else if (key === 'root') {
        els.badgeRoot.classList.remove('dimmed');
        els.badgeRoot.classList.add('active-root');
        els.eqRoot.classList.remove('dimmed');
        els.eqRoot.classList.add('active-root');
        els.pillSquare.classList.remove('dimmed');
        els.pillRoot.classList.remove('dimmed');
      } else if (key === 'square-rel') {
        els.pillSquare.classList.remove('dimmed');
        els.pillSquare.classList.add('active');
        els.badgeRoot.classList.remove('dimmed');
        els.eqRoot.classList.remove('dimmed');
        els.badgeRadicand.classList.remove('dimmed');
        els.eqRadicand.classList.remove('dimmed');
      } else if (key === 'root-rel') {
        els.pillRoot.classList.remove('dimmed');
        els.pillRoot.classList.add('active');
        allInteractive.forEach(el => el.classList.remove('dimmed'));
      }
    }
  </script>
</body>
</html>

Understanding Perfect Squares and Evaluating Square Roots

<!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;
      color: #1e2945;
      background: #ffffff;
      padding: 12px;
      display: flex;
      flex-direction: column;
      align-items: center;
      justify-content: center;
      min-height: 100%;
    }

    .dashboard {
      width: 100%;
      max-width: 580px;
      display: flex;
      flex-direction: column;
      gap: 12px;
    }

    .grid {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 10px;
      position: relative;
    }

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

    .item {
      display: flex;
      align-items: center;
      justify-content: space-between;
      padding: 8px 14px;
      background: #f8fafc;
      border: 1.5px solid #e2e8f0;
      border-radius: 8px;
      cursor: pointer;
      user-select: none;
      transition: background 0.2s ease, border-color 0.2s ease, box-shadow 0.2s ease;
    }

    .item:hover {
      background: #f1f5f9;
      border-color: #cbd5e1;
    }

    .item.active {
      border-color: #22b7ff;
      background: #f0f9ff;
      box-shadow: 0 0 0 2px rgba(34, 183, 255, 0.25);
    }

    .item.swap-item {
      border-color: #f59e0b;
      background: #fffbeb;
    }

    .item.swap-item.active {
      box-shadow: 0 0 0 2px rgba(245, 158, 11, 0.35);
    }

    .expr {
      font-weight: 700;
      font-size: 15px;
      color: #1e2945;
      display: flex;
      align-items: baseline;
      gap: 2px;
    }

    .expr sup {
      font-size: 11px;
      color: #22b7ff;
      font-weight: 800;
    }

    .swap-item .expr sup {
      color: #d97706;
    }

    .eq {
      color: #94a3b8;
      font-weight: 600;
      font-size: 14px;
      margin: 0 6px;
    }

    .val {
      font-family: ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, monospace;
      font-weight: 800;
      font-size: 16px;
      color: #0f172a;
      letter-spacing: 0.5px;
    }

    .swap-digits {
      color: #d97706;
      background: rgba(245, 158, 11, 0.18);
      padding: 1px 3px;
      border-radius: 4px;
    }

    /* Swap connector badge */
    .swap-badge-container {
      position: relative;
    }

    .swap-badge {
      display: flex;
      align-items: center;
      justify-content: center;
      gap: 6px;
      background: #d97706;
      color: #ffffff;
      font-size: 11px;
      font-weight: 700;
      padding: 4px 10px;
      border-radius: 12px;
      margin: -2px auto;
      width: fit-content;
      box-shadow: 0 2px 5px rgba(217, 119, 6, 0.25);
      z-index: 2;
    }

    .swap-arrow {
      font-size: 13px;
      line-height: 1;
    }

    /* Footer interaction cue */
    .hint {
      text-align: center;
      font-size: 12px;
      font-weight: 600;
      color: #64748b;
      display: flex;
      align-items: center;
      justify-content: center;
      gap: 6px;
    }

    .dot-accent {
      width: 6px;
      height: 6px;
      background: #22b7ff;
      border-radius: 50%;
      display: inline-block;
    }

    @media (max-width: 420px) {
      .item {
        padding: 6px 10px;
      }
      .expr {
        font-size: 14px;
      }
      .val {
        font-size: 14px;
      }
      .swap-badge {
        font-size: 10px;
        padding: 3px 8px;
      }
    }
  </style>
</head>
<body>

<div class="dashboard">
  <div class="grid">
    
    <div class="col">
      <div class="item" onclick="selectItem(this)">
        <span class="expr">11<sup>2</sup></span>
        <span><span class="eq">=</span><span class="val">121</span></span>
      </div>

      <div class="item" onclick="selectItem(this)">
        <span class="expr">12<sup>2</sup></span>
        <span><span class="eq">=</span><span class="val">144</span></span>
      </div>

      <div class="item swap-item" onclick="selectItem(this)">
        <span class="expr">13<sup>2</sup></span>
        <span><span class="eq">=</span><span class="val">1<span class="swap-digits">69</span></span></span>
      </div>

      <div class="swap-badge">
        <span>69</span>
        <span class="swap-arrow">⇄</span>
        <span>96</span>
      </div>

      <div class="item swap-item" onclick="selectItem(this)">
        <span class="expr">14<sup>2</sup></span>
        <span><span class="eq">=</span><span class="val">1<span class="swap-digits">96</span></span></span>
      </div>

      <div class="item" onclick="selectItem(this)">
        <span class="expr">15<sup>2</sup></span>
        <span><span class="eq">=</span><span class="val">225</span></span>
      </div>
    </div>

    
    <div class="col">
      <div class="item" onclick="selectItem(this)">
        <span class="expr">16<sup>2</sup></span>
        <span><span class="eq">=</span><span class="val">256</span></span>
      </div>

      <div class="item" onclick="selectItem(this)">
        <span class="expr">17<sup>2</sup></span>
        <span><span class="eq">=</span><span class="val">289</span></span>
      </div>

      <div class="item" onclick="selectItem(this)">
        <span class="expr">18<sup>2</sup></span>
        <span><span class="eq">=</span><span class="val">324</span></span>
      </div>

      <div class="item" onclick="selectItem(this)">
        <span class="expr">19<sup>2</sup></span>
        <span><span class="eq">=</span><span class="val">361</span></span>
      </div>

      <div class="item" onclick="selectItem(this)">
        <span class="expr">20<sup>2</sup></span>
        <span><span class="eq">=</span><span class="val">400</span></span>
      </div>
    </div>
  </div>

  <div class="hint">
    <span class="dot-accent"></span>
    <span>Tap any benchmark square to focus</span>
  </div>
</div>

<script>
  function selectItem(el) {
    const items = document.querySelectorAll('.item');
    const wasActive = el.classList.contains('active');
    items.forEach(item => item.classList.remove('active'));
    if (!wasActive) {
      el.classList.add('active');
    }
  }
</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>
    :root {
      --primary: #0284c7;
      --primary-bright: #22b7ff;
      --primary-soft: rgba(34, 183, 255, 0.14);
      --text: #1e2945;
      --muted: #475569;
      --bg: #f8f9fa;
      --card-bg: #ffffff;
      --border: #cbd5e1;
      --border-light: #e2e8f0;
      --success: #059669;
      --success-soft: #ecfdf5;
      --success-border: #a7f3d0;
      --success-dark: #065f46;
    }

    * {
      box-sizing: border-box;
      margin: 0;
      padding: 0;
    }

    body {
      font-family: system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
      background: var(--bg);
      color: var(--text);
      display: flex;
      flex-direction: column;
      align-items: center;
      justify-content: center;
      padding: 12px 14px;
      min-height: 100vh;
    }

    .main-layout {
      width: 100%;
      max-width: 520px;
      display: flex;
      flex-direction: column;
      gap: 10px;
    }

    /* Stepper Navigation */
    .stepper-nav {
      display: flex;
      align-items: center;
      width: 100%;
    }

    .step-tabs {
      display: flex;
      gap: 6px;
      width: 100%;
    }

    .step-tab {
      flex: 1;
      display: flex;
      align-items: center;
      justify-content: center;
      gap: 6px;
      padding: 6px 8px;
      background: var(--card-bg);
      border: 1.5px solid var(--border);
      border-radius: 20px;
      font-size: 12.5px;
      font-weight: 600;
      color: var(--muted);
      cursor: pointer;
      user-select: none;
      transition: background 0.2s, border-color 0.2s, color 0.2s;
    }

    .step-tab.active {
      background: var(--primary-soft);
      border-color: var(--primary);
      color: var(--text);
    }

    .step-tab.completed {
      border-color: var(--success);
      color: var(--text);
    }

    .step-badge {
      display: inline-flex;
      align-items: center;
      justify-content: center;
      width: 18px;
      height: 18px;
      border-radius: 50%;
      background: #64748b;
      color: #ffffff;
      font-size: 11px;
      font-weight: 700;
      line-height: 1;
      flex-shrink: 0;
      transition: background 0.2s ease;
    }

    .step-tab.active .step-badge {
      background: var(--primary);
    }

    .step-tab.completed .step-badge {
      background: var(--success);
    }

    /* Calculation Cards */
    .steps-container {
      display: flex;
      flex-direction: column;
      gap: 8px;
    }

    .step-card {
      background: var(--card-bg);
      border: 1.5px solid var(--border);
      border-radius: 12px;
      padding: 8px 14px;
      min-height: 52px;
      display: flex;
      align-items: center;
      justify-content: space-between;
      transition: border-color 0.25s, box-shadow 0.25s, opacity 0.25s;
      opacity: 0.65;
    }

    .step-card.active {
      opacity: 1;
      border-color: var(--primary-bright);
      box-shadow: 0 3px 12px rgba(2, 132, 199, 0.15);
      background: #ffffff;
    }

    .step-card.past {
      opacity: 0.95;
      border-color: var(--border);
      background: #ffffff;
    }

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

    .step-circle {
      width: 26px;
      height: 26px;
      border-radius: 50%;
      background: #e2e8f0;
      color: #334155;
      display: flex;
      align-items: center;
      justify-content: center;
      font-size: 13px;
      font-weight: 700;
      flex-shrink: 0;
      transition: background 0.2s, color 0.2s;
    }

    .step-card.active .step-circle {
      background: var(--primary-bright);
      color: #ffffff;
    }

    .step-card.past .step-circle {
      background: var(--success);
      color: #ffffff;
    }

    .step-label {
      font-size: 13.5px;
      font-weight: 600;
      color: var(--muted);
    }

    .step-card.active .step-label {
      color: var(--text);
      font-weight: 700;
    }

    .step-card.past .step-label {
      color: var(--text);
    }

    .step-math {
      font-size: 18px;
      color: var(--text);
      display: inline-flex;
      align-items: center;
      font-family: "Cambria Math", "STIX Two Math", "Georgia", "Times New Roman", serif;
    }

    /* Verification Badge Card */
    .verify-card {
      background: #f8fafc;
      border: 1.5px solid var(--border);
      border-radius: 12px;
      padding: 9px 14px;
      min-height: 52px;
      display: flex;
      align-items: center;
      justify-content: space-between;
      transition: border-color 0.25s, box-shadow 0.25s, opacity 0.25s;
      opacity: 0.65;
    }

    .verify-card.active {
      opacity: 1;
      background: var(--success-soft);
      border-color: var(--success);
      box-shadow: 0 3px 12px rgba(5, 150, 105, 0.15);
    }

    .verify-tag {
      display: inline-flex;
      align-items: center;
      gap: 6px;
      font-size: 13px;
      font-weight: 700;
      color: var(--muted);
    }

    .verify-card.active .verify-tag {
      color: var(--success-dark);
    }

    .verify-badge-icon {
      width: 22px;
      height: 22px;
      border-radius: 50%;
      background: #64748b;
      color: #ffffff;
      display: flex;
      align-items: center;
      justify-content: center;
      font-size: 12px;
      font-weight: 700;
    }

    .verify-card.active .verify-badge-icon {
      background: var(--success);
    }

    .verify-math {
      font-size: 15.5px;
      color: var(--text);
      display: inline-flex;
      align-items: center;
      font-family: "Cambria Math", "STIX Two Math", "Georgia", "Times New Roman", serif;
    }

    .verify-card.active .verify-math {
      color: var(--success-dark);
      font-weight: 600;
    }

    /* Native Math Layouts */
    .m-frac {
      display: inline-flex;
      flex-direction: column;
      vertical-align: middle;
      text-align: center;
      padding: 0 3px;
      line-height: 1.15;
      font-size: 0.95em;
    }

    .m-num {
      border-bottom: 1.8px solid currentColor;
      padding-bottom: 2px;
      display: block;
    }

    .m-den {
      padding-top: 2px;
      display: block;
    }

    .m-rad {
      display: inline-flex;
      align-items: center;
      vertical-align: middle;
    }

    .m-rad-sym {
      display: inline-block;
      flex-shrink: 0;
    }

    .m-rad-body {
      border-top: 1.8px solid currentColor;
      padding-top: 1px;
      padding-left: 2px;
      padding-right: 2px;
      display: inline-flex;
      align-items: center;
    }

    .m-paren {
      font-size: 1.25em;
      line-height: 1;
      vertical-align: middle;
      font-weight: 300;
    }

    .m-sup {
      font-size: 0.7em;
      vertical-align: super;
      margin-left: 1px;
      margin-right: 4px;
      font-weight: bold;
    }

    .m-op {
      margin: 0 4px;
    }

    /* Controls */
    .controls {
      display: flex;
      align-items: center;
      justify-content: center;
      gap: 10px;
      margin-top: 4px;
    }

    .ctrl-btn {
      display: inline-flex;
      align-items: center;
      justify-content: center;
      gap: 4px;
      padding: 6px 14px;
      border-radius: 8px;
      border: 1.5px solid var(--border);
      background: var(--card-bg);
      color: var(--text);
      font-size: 12.5px;
      font-weight: 600;
      cursor: pointer;
      user-select: none;
      transition: background 0.15s, border-color 0.15s;
    }

    .ctrl-btn:active {
      background: #e2e8f0;
    }

    .ctrl-btn.primary {
      background: var(--primary);
      border-color: var(--primary);
      color: #ffffff;
    }

    .ctrl-btn.primary:active {
      background: #0369a1;
    }

    @media (max-width: 420px) {
      body {
        padding: 8px 10px;
      }
      .step-tab {
        font-size: 11px;
        padding: 5px 4px;
        gap: 4px;
      }
      .step-badge {
        width: 16px;
        height: 16px;
        font-size: 10px;
      }
      .step-card, .verify-card {
        padding: 8px 10px;
      }
      .step-label {
        font-size: 12px;
      }
      .step-math {
        font-size: 16px;
      }
      .verify-math {
        font-size: 13px;
      }
      .m-op {
        margin: 0 2px;
      }
    }
  </style>
</head>
<body>

<div class="main-layout">
  
  <div class="stepper-nav">
    <div class="step-tabs">
      <div class="step-tab active" data-step="0">
        <span class="step-badge">1</span>
        <span>Original</span>
      </div>
      <div class="step-tab" data-step="1">
        <span class="step-badge">2</span>
        <span>Split</span>
      </div>
      <div class="step-tab" data-step="2">
        <span class="step-badge">3</span>
        <span>Evaluate</span>
      </div>
      <div class="step-tab" data-step="3">
        <span class="step-badge">✓</span>
        <span>Check</span>
      </div>
    </div>
  </div>

  
  <div class="steps-container">
    
    <div class="step-card active" id="card-0">
      <div class="step-left">
        <div class="step-circle">1</div>
        <span class="step-label">Radical of fraction</span>
      </div>
      <div class="step-math">
        <div class="m-rad">
          <svg class="m-rad-sym" width="14" height="38" viewBox="0 0 14 38" fill="none" stroke="currentColor" stroke-width="1.8" stroke-linecap="round" stroke-linejoin="round">
            <path d="M1 22 L3.5 22 L6 34 L13 2" />
          </svg>
          <div class="m-rad-body">
            <span class="m-frac">
              <span class="m-num">49</span>
              <span class="m-den">81</span>
            </span>
          </div>
        </div>
      </div>
    </div>

    
    <div class="step-card" id="card-1">
      <div class="step-left">
        <div class="step-circle">2</div>
        <span class="step-label">Split square root</span>
      </div>
      <div class="step-math">
        <span class="m-frac">
          <span class="m-num">
            <span class="m-rad">
              <svg class="m-rad-sym" width="12" height="20" viewBox="0 0 12 20" fill="none" stroke="currentColor" stroke-width="1.8" stroke-linecap="round" stroke-linejoin="round">
                <path d="M1 11 L3 11 L5 18 L11 2" />
              </svg>
              <span class="m-rad-body">49</span>
            </span>
          </span>
          <span class="m-den">
            <span class="m-rad">
              <svg class="m-rad-sym" width="12" height="20" viewBox="0 0 12 20" fill="none" stroke="currentColor" stroke-width="1.8" stroke-linecap="round" stroke-linejoin="round">
                <path d="M1 11 L3 11 L5 18 L11 2" />
              </svg>
              <span class="m-rad-body">81</span>
            </span>
          </span>
        </span>
      </div>
    </div>

    
    <div class="step-card" id="card-2">
      <div class="step-left">
        <div class="step-circle">3</div>
        <span class="step-label">Evaluate roots</span>
      </div>
      <div class="step-math">
        <span class="m-frac">
          <span class="m-num">7</span>
          <span class="m-den">9</span>
        </span>
      </div>
    </div>
  </div>

  
  <div class="verify-card" id="card-3">
    <div class="verify-tag">
      <span class="verify-badge-icon">✓</span>
      <span>Verify</span>
    </div>
    <div class="verify-math">
      <span class="m-paren">(</span><span class="m-frac"><span class="m-num">7</span><span class="m-den">9</span></span><span class="m-paren">)</span><sup class="m-sup">2</sup>
      <span class="m-op">=</span>
      <span class="m-frac"><span class="m-num">7 &times; 7</span><span class="m-den">9 &times; 9</span></span>
      <span class="m-op">=</span>
      <span class="m-frac"><span class="m-num">49</span><span class="m-den">81</span></span>
    </div>
  </div>

  
  <div class="controls">
    <button class="ctrl-btn" id="prevBtn" type="button">← Prev</button>
    <button class="ctrl-btn primary" id="playBtn" type="button">Pause ⏸</button>
    <button class="ctrl-btn" id="nextBtn" type="button">Next →</button>
  </div>
</div>

<script>
  let currentStep = 0;
  const totalSteps = 4;
  let timer = null;
  let isPlaying = true;

  const tabs = document.querySelectorAll('.step-tab');
  const cards = [
    document.getElementById('card-0'),
    document.getElementById('card-1'),
    document.getElementById('card-2'),
    document.getElementById('card-3')
  ];
  const playBtn = document.getElementById('playBtn');
  const prevBtn = document.getElementById('prevBtn');
  const nextBtn = document.getElementById('nextBtn');

  function updateView(step) {
    currentStep = step;

    tabs.forEach((tab, idx) => {
      tab.classList.remove('active', 'completed');
      if (idx === currentStep) {
        tab.classList.add('active');
      } else if (idx < currentStep) {
        tab.classList.add('completed');
      }
    });

    cards.forEach((card, idx) => {
      card.classList.remove('active', 'past');
      if (idx === currentStep) {
        card.classList.add('active');
      } else if (idx < currentStep) {
        card.classList.add('past');
      }
    });
  }

  function nextStep() {
    updateView((currentStep + 1) % totalSteps);
  }

  function prevStep() {
    updateView((currentStep - 1 + totalSteps) % totalSteps);
  }

  function startAutoPlay() {
    stopAutoPlay();
    isPlaying = true;
    playBtn.textContent = 'Pause ⏸';
    timer = setInterval(nextStep, 3500);
  }

  function stopAutoPlay() {
    isPlaying = false;
    playBtn.textContent = 'Play ▶';
    if (timer) {
      clearInterval(timer);
      timer = null;
    }
  }

  function togglePlay() {
    if (isPlaying) {
      stopAutoPlay();
    } else {
      startAutoPlay();
    }
  }

  tabs.forEach((tab, index) => {
    tab.addEventListener('click', () => {
      stopAutoPlay();
      updateView(index);
    });
  });

  playBtn.addEventListener('click', togglePlay);

  prevBtn.addEventListener('click', () => {
    stopAutoPlay();
    prevStep();
  });

  nextBtn.addEventListener('click', () => {
    stopAutoPlay();
    nextStep();
  });

  startAutoPlay();
</script>

</body>
</html>

<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>Square Numbers Geometric Area Progression</title>
  <style>
    * { 
      box-sizing: border-box; 
      margin: 0; 
      padding: 0; 
    }
    
    html, body {
      width: 100%;
      font-family: system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
      background: transparent;
      color: #0f172a;
      display: flex;
      align-items: center;
      justify-content: center;
      user-select: none;
      -webkit-user-select: none;
      overflow-x: hidden;
    }

    .canvas {
      width: 100%;
      max-width: 600px;
      padding: 12px 8px;
      display: flex;
      flex-direction: column;
      align-items: center;
      justify-content: center;
    }

    .progression {
      display: flex;
      flex-wrap: wrap;
      align-items: flex-end;
      justify-content: center;
      gap: 12px 16px;
      width: 100%;
    }

    .square-col {
      display: flex;
      flex-direction: column;
      align-items: center;
      cursor: pointer;
      padding: 6px 8px;
      border-radius: 8px;
      transition: background-color 0.2s ease, box-shadow 0.2s ease;
    }

    .square-col:hover {
      background-color: rgba(2, 132, 199, 0.06);
    }

    .square-col.active {
      background-color: rgba(2, 132, 199, 0.1);
      box-shadow: 0 0 0 1.5px rgba(2, 132, 199, 0.4);
    }

    .dim-top {
      font-size: 14px;
      font-weight: 700;
      color: #0284c7;
      margin-bottom: 4px;
      height: 18px;
      line-height: 18px;
      text-align: center;
      padding-left: 16px;
    }

    .grid-row-wrap {
      display: flex;
      align-items: center;
      justify-content: center;
    }

    .dim-left {
      font-size: 14px;
      font-weight: 700;
      color: #0284c7;
      margin-right: 4px;
      width: 16px;
      text-align: right;
      flex-shrink: 0;
    }

    .grid-box {
      border-radius: 4px;
      overflow: hidden;
      display: grid;
      box-shadow: 0 1px 3px rgba(2, 132, 199, 0.2);
      position: relative;
      flex-shrink: 0;
    }

    /* Grid 1x1 */
    .grid-1 {
      width: 36px;
      height: 36px;
      grid-template-columns: 1fr;
      background: #0284c7;
      border: 1.5px solid #0284c7;
    }

    /* Grid 2x2 */
    .grid-2 {
      width: 60px;
      height: 60px;
      grid-template-columns: repeat(2, 1fr);
      background: #ffffff;
      gap: 1.5px;
      border: 1.5px solid #0284c7;
    }
    .grid-2 .cell {
      background: #0284c7;
    }

    /* Grid 3x3 */
    .grid-3 {
      width: 84px;
      height: 84px;
      grid-template-columns: repeat(3, 1fr);
      background: #ffffff;
      gap: 1.5px;
      border: 1.5px solid #0284c7;
    }
    .grid-3 .cell {
      background: #0284c7;
    }

    /* Grid 12x12 */
    .grid-12 {
      width: 144px;
      height: 144px;
      grid-template-columns: repeat(12, 1fr);
      background: #38bdf8;
      gap: 1px;
      border: 1.5px solid #0284c7;
    }
    .grid-12 .cell {
      background: #e0f2fe;
      transition: background-color 0.15s ease;
    }
    .square-col.active .grid-12 .cell {
      background: #bae6fd;
    }

    .pill-overlay {
      position: absolute;
      inset: 0;
      display: flex;
      align-items: center;
      justify-content: center;
      pointer-events: none;
    }

    .pill-tag {
      background: rgba(15, 23, 42, 0.88);
      color: #ffffff;
      font-size: 11px;
      font-weight: 600;
      padding: 3px 8px;
      border-radius: 999px;
      backdrop-filter: blur(2px);
      box-shadow: 0 2px 5px rgba(0, 0, 0, 0.25);
      white-space: nowrap;
    }

    .equation-label {
      margin-top: 8px;
      font-size: 13px;
      font-weight: 700;
      color: #0f172a;
      display: flex;
      align-items: center;
      gap: 4px;
      white-space: nowrap;
    }

    .badge {
      background: #f0f9ff;
      color: #0284c7;
      border: 1px solid #bae6fd;
      padding: 1px 6px;
      border-radius: 4px;
      font-weight: 800;
    }

    /* Responsive adjustments for mobile viewports */
    @media (max-width: 480px) {
      .canvas {
        padding: 8px 4px;
      }
      .progression {
        gap: 8px 10px;
      }
      .square-col {
        padding: 4px;
      }
      .dim-top {
        font-size: 12px;
        height: 15px;
        line-height: 15px;
        padding-left: 14px;
      }
      .dim-left {
        font-size: 12px;
        width: 14px;
        margin-right: 3px;
      }
      .grid-1 {
        width: 32px;
        height: 32px;
      }
      .grid-2 {
        width: 52px;
        height: 52px;
      }
      .grid-3 {
        width: 72px;
        height: 72px;
      }
      .grid-12 {
        width: 124px;
        height: 124px;
      }
      .pill-tag {
        font-size: 10px;
        padding: 2px 6px;
      }
      .equation-label {
        font-size: 12px;
        margin-top: 6px;
      }
    }

    @media (max-width: 340px) {
      .grid-12 {
        width: 110px;
        height: 110px;
      }
      .progression {
        gap: 6px 8px;
      }
    }
  </style>
</head>
<body>
  <div class="canvas">
    <div class="progression">
      
      <div class="square-col" onclick="pulse(this)" title="1 × 1 = 1">
        <div class="dim-top">1</div>
        <div class="grid-row-wrap">
          <div class="dim-left">1</div>
          <div class="grid-box grid-1"></div>
        </div>
        <div class="equation-label">1² = <span class="badge">1</span></div>
      </div>

      
      <div class="square-col" onclick="pulse(this)" title="2 × 2 = 4">
        <div class="dim-top">2</div>
        <div class="grid-row-wrap">
          <div class="dim-left">2</div>
          <div class="grid-box grid-2">
            <div class="cell"></div><div class="cell"></div>
            <div class="cell"></div><div class="cell"></div>
          </div>
        </div>
        <div class="equation-label">2² = <span class="badge">4</span></div>
      </div>

      
      <div class="square-col" onclick="pulse(this)" title="3 × 3 = 9">
        <div class="dim-top">3</div>
        <div class="grid-row-wrap">
          <div class="dim-left">3</div>
          <div class="grid-box grid-3">
            <div class="cell"></div><div class="cell"></div><div class="cell"></div>
            <div class="cell"></div><div class="cell"></div><div class="cell"></div>
            <div class="cell"></div><div class="cell"></div><div class="cell"></div>
          </div>
        </div>
        <div class="equation-label">3² = <span class="badge">9</span></div>
      </div>

      
      <div class="square-col active" onclick="pulse(this)" title="12 × 12 = 144">
        <div class="dim-top">12</div>
        <div class="grid-row-wrap">
          <div class="dim-left">12</div>
          <div class="grid-box grid-12" id="grid12">
            <div class="pill-overlay">
              <span class="pill-tag">Area = 144</span>
            </div>
          </div>
        </div>
        <div class="equation-label">12² = <span class="badge">144</span></div>
      </div>
    </div>
  </div>

  <script>
    // Populate the 144 cells for the 12x12 grid
    const g12 = document.getElementById('grid12');
    const overlay = g12.querySelector('.pill-overlay');
    for (let i = 0; i < 144; i++) {
      const cell = document.createElement('div');
      cell.className = 'cell';
      g12.insertBefore(cell, overlay);
    }

    function pulse(el) {
      document.querySelectorAll('.square-col').forEach(c => c.classList.remove('active'));
      el.classList.add('active');
    }
  </script>
</body>
</html>

OGM.8.NO.5

Aligned learning resources

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