<!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: transparent;
      padding: 12px;
      display: flex;
      flex-direction: column;
      gap: 14px;
      width: 100%;
      min-height: 100%;
      justify-content: center;
    }
    .track {
      background: #f8fafc;
      border-radius: 12px;
      padding: 12px 10px;
      display: flex;
      flex-direction: column;
      gap: 8px;
    }
    .track-header {
      display: flex;
      align-items: center;
      justify-content: space-between;
      font-size: 13px;
      font-weight: 700;
      padding: 0 4px;
    }
    .bad { color: #dc2626; }
    .good { color: #16a34a; }
    .sequence-row {
      display: flex;
      align-items: center;
      justify-content: space-between;
      position: relative;
      padding: 18px 4px 4px 4px;
    }
    .node-wrap {
      display: flex;
      flex-direction: column;
      align-items: center;
      position: relative;
      z-index: 2;
    }
    .node {
      width: 38px;
      height: 38px;
      border-radius: 50%;
      background: #ffffff;
      border: 2px solid #cbd5e1;
      display: flex;
      align-items: center;
      justify-content: center;
      font-size: 14px;
      font-weight: 700;
      color: #1e2945;
      box-shadow: 0 1px 3px rgba(0,0,0,0.06);
      transition: all 0.25s ease;
    }
    .node.error {
      border-color: #ef4444;
      background: #fef2f2;
      color: #dc2626;
    }
    .node.target {
      border-color: #0284c7;
      background: #0284c7;
      color: #ffffff;
      box-shadow: 0 2px 8px rgba(2, 132, 199, 0.35);
      border-radius: 10px;
      width: 44px;
    }
    .jump {
      flex: 1;
      display: flex;
      flex-direction: column;
      align-items: center;
      position: relative;
      margin-top: -16px;
    }
    .jump-tag {
      font-size: 11px;
      font-weight: 700;
      padding: 1px 5px;
      border-radius: 6px;
      margin-bottom: 2px;
      white-space: nowrap;
      z-index: 3;
    }
    .jump-tag.red {
      background: #fee2e2;
      color: #dc2626;
    }
    .jump-tag.green {
      background: #dcfce7;
      color: #15803d;
    }
    .jump-tag.blue {
      background: #e0f2fe;
      color: #0284c7;
    }
    .jump svg {
      width: 100%;
      height: 18px;
      overflow: visible;
    }
    .result-box {
      font-size: 12px;
      font-weight: 700;
      text-align: center;
      padding: 4px 8px;
      border-radius: 6px;
      margin-top: 2px;
    }
    .result-box.bad {
      background: #fef2f2;
      color: #dc2626;
      border: 1px dashed #fca5a5;
    }
    .result-box.good {
      background: #f0fdf4;
      color: #16a34a;
      border: 1px solid #bbf7d0;
    }
    .highlight-pill {
      background: #0284c7;
      color: white;
      font-size: 12px;
      font-weight: 700;
      padding: 3px 8px;
      border-radius: 6px;
      display: inline-block;
    }
  </style>
</head>
<body>

  
  <div class="track">
    <div class="track-header bad">
      <span>Addition Check</span>
      <span>❌ Fails</span>
    </div>
    <div class="sequence-row">
      <div class="node-wrap">
        <div class="node">2</div>
      </div>

      <div class="jump">
        <span class="jump-tag red">+4</span>
        <svg viewBox="0 0 50 20">
          <path d="M 5,18 Q 25,2 45,18" fill="none" stroke="#ef4444" stroke-width="2" stroke-dasharray="3,2" />
        </svg>
      </div>

      <div class="node-wrap">
        <div class="node">6</div>
      </div>

      <div class="jump">
        <span class="jump-tag red">+4</span>
        <svg viewBox="0 0 50 20">
          <path d="M 5,18 Q 25,2 45,18" fill="none" stroke="#ef4444" stroke-width="2" stroke-dasharray="3,2" />
        </svg>
      </div>

      <div class="node-wrap">
        <div class="node error">10</div>
      </div>
    </div>
    <div class="result-box bad">6 + 4 = 10 (Not 18)</div>
  </div>

  
  <div class="track">
    <div class="track-header good">
      <span>Multiplication Check</span>
      <span>✅ Pattern: ×3</span>
    </div>
    <div class="sequence-row">
      <div class="node-wrap">
        <div class="node">2</div>
      </div>

      <div class="jump">
        <span class="jump-tag green">×3</span>
        <svg viewBox="0 0 40 20">
          <path d="M 4,18 Q 20,2 36,18" fill="none" stroke="#22c55e" stroke-width="2" />
        </svg>
      </div>

      <div class="node-wrap">
        <div class="node">6</div>
      </div>

      <div class="jump">
        <span class="jump-tag green">×3</span>
        <svg viewBox="0 0 40 20">
          <path d="M 4,18 Q 20,2 36,18" fill="none" stroke="#22c55e" stroke-width="2" />
        </svg>
      </div>

      <div class="node-wrap">
        <div class="node">18</div>
      </div>

      <div class="jump">
        <span class="jump-tag green">×3</span>
        <svg viewBox="0 0 40 20">
          <path d="M 4,18 Q 20,2 36,18" fill="none" stroke="#22c55e" stroke-width="2" />
        </svg>
      </div>

      <div class="node-wrap">
        <div class="node">54</div>
      </div>

      <div class="jump">
        <span class="jump-tag blue">×3</span>
        <svg viewBox="0 0 40 20">
          <path d="M 4,18 Q 20,2 36,18" fill="none" stroke="#0284c7" stroke-width="2.5" />
        </svg>
      </div>

      <div class="node-wrap">
        <div class="node target">162</div>
      </div>
    </div>
    <div class="result-box good">
      <span class="highlight-pill">54 × 3 = 162</span>
    </div>
  </div>

</body>
</html>

Identifying and Extending Increasing Number Patterns

<!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;
      font-family: system-ui, -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    }

    body {
      width: 100%;
      background: #f8fafc;
      color: #1e293b;
      padding: 14px;
      display: flex;
      flex-direction: column;
      align-items: center;
      justify-content: center;
      gap: 12px;
    }

    /* Target Sequence */
    .sequence-container {
      width: 100%;
      max-width: 360px;
      display: flex;
      justify-content: space-between;
      align-items: center;
      gap: 6px;
    }

    .tile {
      flex: 1;
      aspect-ratio: 1;
      max-width: 60px;
      background: #ffffff;
      border: 2px solid #cbd5e1;
      border-radius: 10px;
      display: flex;
      align-items: center;
      justify-content: center;
      font-size: 18px;
      font-weight: 700;
      color: #334155;
      box-shadow: 0 1px 3px rgba(0,0,0,0.05);
      transition: all 0.3s ease;
    }

    .tile.target {
      border-color: #0284c7;
      background: #f0f9ff;
      color: #0284c7;
      box-shadow: 0 0 0 3px rgba(2, 132, 199, 0.2), 0 2px 6px rgba(2, 132, 199, 0.15);
      font-size: 20px;
    }

    /* Path Cards */
    .paths-wrapper {
      width: 100%;
      max-width: 360px;
      display: flex;
      flex-direction: column;
      gap: 10px;
    }

    .path-card {
      background: #ffffff;
      border: 2px solid #e2e8f0;
      border-radius: 12px;
      padding: 10px 12px;
      display: flex;
      flex-direction: column;
      gap: 8px;
      cursor: pointer;
      transition: border-color 0.25s ease, box-shadow 0.25s ease;
    }

    .path-card.active-success {
      border-color: #0284c7;
      box-shadow: 0 0 0 2px rgba(2, 132, 199, 0.2);
    }

    .path-card.active-fail {
      border-color: #ef4444;
      box-shadow: 0 0 0 2px rgba(239, 68, 68, 0.15);
    }

    .path-header {
      display: flex;
      justify-content: space-between;
      align-items: center;
      font-size: 13px;
      font-weight: 700;
    }

    .rule-title {
      display: flex;
      align-items: center;
      gap: 6px;
      color: #475569;
    }

    .badge {
      font-size: 12px;
      padding: 2px 8px;
      border-radius: 12px;
      display: inline-flex;
      align-items: center;
      gap: 4px;
      font-weight: 700;
    }

    .badge-fail {
      background: #fef2f2;
      color: #dc2626;
      border: 1px solid #fecaca;
    }

    .badge-success {
      background: #f0fdf4;
      color: #16a34a;
      border: 1px solid #bbf7d0;
    }

    /* Step Sequence Row */
    .steps-row {
      display: flex;
      align-items: center;
      justify-content: space-between;
      gap: 2px;
    }

    .mini-node {
      font-size: 14px;
      font-weight: 700;
      color: #334155;
      min-width: 24px;
      text-align: center;
    }

    .mini-node.wrong {
      color: #dc2626;
      text-decoration: line-through;
    }

    .mini-node.correct {
      color: #0284c7;
      font-weight: 800;
      font-size: 16px;
    }

    .op-pill {
      font-size: 11px;
      font-weight: 700;
      color: #64748b;
      background: #f1f5f9;
      padding: 2px 5px;
      border-radius: 6px;
      white-space: nowrap;
    }

    .op-pill.correct {
      color: #0284c7;
      background: #e0f2fe;
    }

    .op-pill.fail {
      color: #dc2626;
      background: #fee2e2;
    }

    .indicator-arrow {
      color: #94a3b8;
      font-size: 11px;
    }
  </style>
</head>
<body>

  
  <div class="sequence-container">
    <div class="tile">4</div>
    <div class="tile">8</div>
    <div class="tile target" id="targetTile">16</div>
    <div class="tile">32</div>
    <div class="tile">64</div>
  </div>

  
  <div class="paths-wrapper">
    
    
    <div class="path-card" id="cardA" onclick="selectPath('A')">
      <div class="path-header">
        <span class="rule-title">+4 Rule</span>
        <span class="badge badge-fail">✕ Fails</span>
      </div>
      <div class="steps-row">
        <span class="mini-node">4</span>
        <span class="op-pill fail">+4</span>
        <span class="mini-node">8</span>
        <span class="op-pill fail">+4</span>
        <span class="mini-node">12</span>
        <span class="op-pill fail">+4</span>
        <span class="mini-node wrong">16</span>
        <span class="indicator-arrow">≠</span>
        <span class="mini-node">32</span>
      </div>
    </div>

    
    <div class="path-card active-success" id="cardB" onclick="selectPath('B')">
      <div class="path-header">
        <span class="rule-title">×2 Rule</span>
        <span class="badge badge-success">✓ Matches</span>
      </div>
      <div class="steps-row">
        <span class="mini-node">4</span>
        <span class="op-pill correct">×2</span>
        <span class="mini-node">8</span>
        <span class="op-pill correct">×2</span>
        <span class="mini-node correct">16</span>
        <span class="op-pill correct">×2</span>
        <span class="mini-node">32</span>
        <span class="op-pill correct">×2</span>
        <span class="mini-node">64</span>
      </div>
    </div>

  </div>

  <script>
    function selectPath(type) {
      const cardA = document.getElementById('cardA');
      const cardB = document.getElementById('cardB');
      const target = document.getElementById('targetTile');

      if (type === 'A') {
        cardA.className = 'path-card active-fail';
        cardB.className = 'path-card';
        target.textContent = '?';
        target.style.color = '#ef4444';
        target.style.borderColor = '#ef4444';
        target.style.background = '#fef2f2';
        target.style.boxShadow = '0 0 0 3px rgba(239, 68, 68, 0.2)';
      } else {
        cardA.className = 'path-card';
        cardB.className = 'path-card active-success';
        target.textContent = '16';
        target.style.color = '#0284c7';
        target.style.borderColor = '#0284c7';
        target.style.background = '#f0f9ff';
        target.style.boxShadow = '0 0 0 3px rgba(2, 132, 199, 0.2), 0 2px 6px rgba(2, 132, 199, 0.15)';
      }
    }
  </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">
  <title>Pattern Hop</title>
  <style>
    * {
      box-sizing: border-box;
      margin: 0;
      padding: 0;
      user-select: none;
      -webkit-user-select: none;
    }

    body {
      width: 100%;
      height: 100%;
      min-height: 100vh;
      background-color: #f8fafc;
      font-family: system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
      color: #1e2945;
      display: flex;
      flex-direction: column;
      align-items: center;
      justify-content: space-between;
      padding: 16px 12px;
      overflow-x: hidden;
    }

    .diagram-area {
      width: 100%;
      max-width: 500px;
      position: relative;
      flex: 1;
      display: flex;
      flex-direction: column;
      justify-content: center;
      align-items: center;
    }

    .svg-scene {
      width: 100%;
      height: auto;
      overflow: visible;
    }

    /* Controls */
    .controls {
      display: flex;
      align-items: center;
      gap: 12px;
      margin-top: 12px;
    }

    .btn {
      background: #ffffff;
      border: 1px solid #cbd5e1;
      color: #1e2945;
      font-size: 14px;
      font-weight: 600;
      padding: 8px 16px;
      border-radius: 8px;
      cursor: pointer;
      display: inline-flex;
      align-items: center;
      gap: 6px;
      transition: background-color 0.2s, box-shadow 0.2s;
    }

    .btn:active {
      background: #f1f5f9;
    }

    .step-dots {
      display: flex;
      gap: 8px;
    }

    .dot {
      width: 10px;
      height: 10px;
      border-radius: 50%;
      background-color: #cbd5e1;
      cursor: pointer;
      transition: background-color 0.3s;
    }

    .dot.active {
      background-color: #0284c7;
    }

    /* Hop text badge */
    .badge-text {
      font-family: system-ui, sans-serif;
      font-size: 13px;
      font-weight: 700;
      fill: #0284c7;
    }

    .pad-text {
      font-family: system-ui, sans-serif;
      font-size: 20px;
      font-weight: 800;
      fill: #065f46;
    }

    .revealed-text {
      font-family: system-ui, sans-serif;
      font-size: 22px;
      font-weight: 800;
      fill: #0284c7;
    }

    .question-text {
      font-family: system-ui, sans-serif;
      font-size: 22px;
      font-weight: 800;
      fill: #64748b;
    }

    /* Transition styles */
    .hop-arc {
      transition: stroke-dashoffset 0.5s ease-in-out, opacity 0.3s ease;
    }

    #frog {
      transition: transform 0.6s cubic-bezier(0.34, 1.4, 0.64, 1);
    }
  </style>
</head>
<body>

  <div class="diagram-area">
    <svg class="svg-scene" viewBox="0 0 350 200" preserveAspectRatio="xMidYMid meet">
      
      <path d="M 10 180 Q 80 175 160 180 T 340 180" fill="none" stroke="#e2e8f0" stroke-width="2" stroke-linecap="round"/>
      <path d="M 30 188 Q 120 184 220 188 T 330 188" fill="none" stroke="#e2e8f0" stroke-width="1.5" stroke-linecap="round"/>

      
      
      <g id="hop-1" opacity="0.15" style="transition: opacity 0.3s ease;">
        <path d="M 40 145 Q 72.5 80 105 145" fill="none" stroke="#0284c7" stroke-width="3" stroke-linecap="round" stroke-dasharray="4 4"/>
        <rect x="58" y="92" width="30" height="20" rx="10" fill="#e0f2fe" stroke="#0284c7" stroke-width="1.5"/>
        <text x="73" y="106" text-anchor="middle" dominant-baseline="central" class="badge-text">+4</text>
      </g>

      
      <g id="hop-2" opacity="0.15" style="transition: opacity 0.3s ease;">
        <path d="M 105 145 Q 138.5 80 172 145" fill="none" stroke="#0284c7" stroke-width="3" stroke-linecap="round" stroke-dasharray="4 4"/>
        <rect x="124" y="92" width="30" height="20" rx="10" fill="#e0f2fe" stroke="#0284c7" stroke-width="1.5"/>
        <text x="139" y="106" text-anchor="middle" dominant-baseline="central" class="badge-text">+4</text>
      </g>

      
      <g id="hop-3" opacity="0.15" style="transition: opacity 0.3s ease;">
        <path d="M 172 145 Q 206 80 240 145" fill="none" stroke="#0284c7" stroke-width="3" stroke-linecap="round" stroke-dasharray="4 4"/>
        <rect x="191" y="92" width="30" height="20" rx="10" fill="#e0f2fe" stroke="#0284c7" stroke-width="1.5"/>
        <text x="206" y="106" text-anchor="middle" dominant-baseline="central" class="badge-text">+4</text>
      </g>

      
      <g id="hop-4" opacity="0.15" style="transition: opacity 0.3s ease;">
        <path d="M 240 145 Q 274 80 308 145" fill="none" stroke="#0284c7" stroke-width="3" stroke-linecap="round" stroke-dasharray="4 4"/>
        <rect x="259" y="92" width="30" height="20" rx="10" fill="#e0f2fe" stroke="#0284c7" stroke-width="1.5"/>
        <text x="274" y="106" text-anchor="middle" dominant-baseline="central" class="badge-text">+4</text>
      </g>

      
      <g transform="translate(40, 160)">
        <ellipse cx="0" cy="0" rx="26" ry="14" fill="#a7f3d0" stroke="#059669" stroke-width="2.5"/>
        <path d="M 0 0 L 18 -10" stroke="#059669" stroke-width="2"/>
        <text x="0" y="2" text-anchor="middle" dominant-baseline="central" class="pad-text">3</text>
      </g>

      
      <g transform="translate(105, 160)">
        <ellipse cx="0" cy="0" rx="26" ry="14" fill="#a7f3d0" stroke="#059669" stroke-width="2.5"/>
        <path d="M 0 0 L 18 -10" stroke="#059669" stroke-width="2"/>
        <text x="0" y="2" text-anchor="middle" dominant-baseline="central" class="pad-text">7</text>
      </g>

      
      <g transform="translate(172, 160)">
        <ellipse cx="0" cy="0" rx="26" ry="14" fill="#a7f3d0" stroke="#059669" stroke-width="2.5"/>
        <path d="M 0 0 L 18 -10" stroke="#059669" stroke-width="2"/>
        <text x="0" y="2" text-anchor="middle" dominant-baseline="central" class="pad-text">11</text>
      </g>

      
      <g transform="translate(240, 160)">
        <ellipse cx="0" cy="0" rx="26" ry="14" fill="#a7f3d0" stroke="#059669" stroke-width="2.5"/>
        <path d="M 0 0 L 18 -10" stroke="#059669" stroke-width="2"/>
        <text x="0" y="2" text-anchor="middle" dominant-baseline="central" class="pad-text">15</text>
      </g>

      
      <g id="target-pad" transform="translate(308, 160)">
        <ellipse id="pad-5-bg" cx="0" cy="0" rx="26" ry="14" fill="#ffffff" stroke="#94a3b8" stroke-width="2.5" stroke-dasharray="5 4"/>
        <text id="q-mark" x="0" y="2" text-anchor="middle" dominant-baseline="central" class="question-text">?</text>
        <text id="ans-val" x="0" y="2" text-anchor="middle" dominant-baseline="central" class="revealed-text" opacity="0">19</text>
      </g>

      
      <g id="frog" transform="translate(40, 138)">
        
        <text x="0" y="0" font-size="30" text-anchor="middle" dominant-baseline="central">🐸</text>
      </g>
    </svg>
  </div>

  
  <div class="controls">
    <button class="btn" id="hopBtn">▶ Next Hop</button>
    <div class="step-dots" id="dotGroup">
      <span class="dot active" data-step="0"></span>
      <span class="dot" data-step="1"></span>
      <span class="dot" data-step="2"></span>
      <span class="dot" data-step="3"></span>
      <span class="dot" data-step="4"></span>
    </div>
  </div>

  <script>
    const frogPositions = [
      { x: 40, y: 138 },
      { x: 105, y: 138 },
      { x: 172, y: 138 },
      { x: 240, y: 138 },
      { x: 308, y: 138 }
    ];

    let currentStep = 0;
    const totalSteps = 5;

    const frog = document.getElementById('frog');
    const hopBtn = document.getElementById('hopBtn');
    const dots = document.querySelectorAll('.dot');
    const qMark = document.getElementById('q-mark');
    const ansVal = document.getElementById('ans-val');
    const pad5Bg = document.getElementById('pad-5-bg');

    function updateStep(step) {
      currentStep = step;

      // Update Frog position
      const pos = frogPositions[currentStep];
      frog.setAttribute('transform', `translate(${pos.x}, ${pos.y})`);

      // Update Hops visibility
      for (let i = 1; i <= 4; i++) {
        const hopEl = document.getElementById(`hop-${i}`);
        if (i <= currentStep) {
          hopEl.setAttribute('opacity', '1');
        } else {
          hopEl.setAttribute('opacity', '0.15');
        }
      }

      // Update target pad state (revealed on step 4)
      if (currentStep === 4) {
        qMark.setAttribute('opacity', '0');
        ansVal.setAttribute('opacity', '1');
        pad5Bg.setAttribute('fill', '#e0f2fe');
        pad5Bg.setAttribute('stroke', '#0284c7');
        pad5Bg.removeAttribute('stroke-dasharray');
        hopBtn.innerHTML = '↺ Reset';
      } else {
        qMark.setAttribute('opacity', '1');
        ansVal.setAttribute('opacity', '0');
        pad5Bg.setAttribute('fill', '#ffffff');
        pad5Bg.setAttribute('stroke', '#94a3b8');
        pad5Bg.setAttribute('stroke-dasharray', '5 4');
        hopBtn.innerHTML = '▶ Next Hop';
      }

      // Update Dots
      dots.forEach((dot, idx) => {
        if (idx === currentStep) {
          dot.classList.add('active');
        } else {
          dot.classList.remove('active');
        }
      });
    }

    hopBtn.addEventListener('click', () => {
      let next = currentStep + 1;
      if (next >= totalSteps) {
        next = 0;
      }
      updateStep(next);
    });

    dots.forEach((dot) => {
      dot.addEventListener('click', () => {
        const step = parseInt(dot.getAttribute('data-step'), 10);
        updateStep(step);
      });
    });

    // Auto loop calmly with pedagogical pacing (3.2s per hop)
    let timer = setInterval(() => {
      let next = (currentStep + 1) % totalSteps;
      updateStep(next);
    }, 3200);

    // Pause auto timer on user interaction
    function pauseAuto() {
      if (timer) {
        clearInterval(timer);
        timer = null;
      }
    }

    hopBtn.addEventListener('click', pauseAuto);
    dots.forEach(d => d.addEventListener('click', pauseAuto));
  </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="1:1">
  <title>Step-by-Step Number Pattern</title>
  <style>
    * {
      box-sizing: border-box;
      margin: 0;
      padding: 0;
      font-family: system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
      -webkit-tap-highlight-color: transparent;
    }

    body {
      background: #ffffff;
      color: #1e2945;
      display: flex;
      flex-direction: column;
      align-items: center;
      justify-content: space-between;
      min-height: 100%;
      padding: 12px 10px;
      user-select: none;
    }

    /* Sequence Display Area */
    .sequence-container {
      width: 100%;
      max-width: 420px;
      display: flex;
      flex-direction: column;
      align-items: center;
      padding: 4px 0 8px 0;
    }

    .hops-row {
      display: flex;
      justify-content: space-between;
      width: 88%;
      height: 32px;
      margin-bottom: 2px;
      position: relative;
    }

    .hop-badge {
      display: flex;
      align-items: center;
      justify-content: center;
      font-size: 13px;
      font-weight: 800;
      border-radius: 20px;
      padding: 2px 10px;
      border: 1.5px solid transparent;
      opacity: 0.15;
      transition: all 0.3s ease;
      background: #f1f5f9;
      color: #64748b;
    }

    .hop-badge.active-1 {
      opacity: 1;
      background: #fef08a;
      border-color: #eab308;
      color: #854d0e;
      transform: translateY(-2px);
    }

    .hop-badge.active-2 {
      opacity: 1;
      background: #bbf7d0;
      border-color: #22c55e;
      color: #15803d;
      transform: translateY(-2px);
    }

    .hop-badge.active-3 {
      opacity: 1;
      background: #0284c7;
      border-color: #0369a1;
      color: #ffffff;
      transform: translateY(-2px);
      box-shadow: 0 3px 8px rgba(2, 132, 199, 0.35);
    }

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

    .num-tile {
      width: 52px;
      height: 52px;
      border-radius: 14px;
      display: flex;
      align-items: center;
      justify-content: center;
      font-size: 20px;
      font-weight: 800;
      background: #f8fafc;
      border: 2px solid #e2e8f0;
      color: #334155;
      transition: all 0.3s ease;
    }

    .num-tile.highlight-yellow {
      border-color: #eab308;
      background: #fef9c3;
      color: #854d0e;
    }

    .num-tile.highlight-green {
      border-color: #22c55e;
      background: #dcfce7;
      color: #166534;
    }

    .num-tile.highlight-blue {
      border-color: #0284c7;
      background: #0284c7;
      color: #ffffff;
      box-shadow: 0 4px 10px rgba(2, 132, 199, 0.3);
    }

    .num-tile.unknown {
      border: 2px dashed #94a3b8;
      color: #0284c7;
    }

    /* Step Cards Stack */
    .steps-list {
      width: 100%;
      max-width: 420px;
      display: flex;
      flex-direction: column;
      gap: 8px;
      margin: 8px 0;
    }

    .step-card {
      display: flex;
      align-items: center;
      padding: 10px 14px;
      border-radius: 12px;
      border: 2px solid rgba(0, 0, 0, 0);
      cursor: pointer;
      opacity: 0.45;
      transition: all 0.3s ease;
    }

    .step-card.active {
      opacity: 1;
      box-shadow: 0 2px 8px rgba(0, 0, 0, 0.06);
    }

    .step-badge {
      font-size: 11px;
      font-weight: 800;
      letter-spacing: 0.5px;
      text-transform: uppercase;
      padding: 4px 8px;
      border-radius: 6px;
      margin-right: 12px;
      flex-shrink: 0;
    }

    .step-content {
      display: flex;
      flex-direction: column;
      gap: 1px;
    }

    .step-title {
      font-size: 13px;
      font-weight: 700;
    }

    .step-math {
      font-size: 15px;
      font-weight: 800;
      font-variant-numeric: tabular-nums;
    }

    /* Card 1: Soft Yellow */
    .card-1 {
      background: #fefce8;
      border-color: #fef08a;
      color: #854d0e;
    }
    .card-1.active {
      border-color: #eab308;
      background: #fef9c3;
    }
    .card-1 .step-badge {
      background: #fef08a;
      color: #854d0e;
      border: 1px solid #ca8a04;
    }

    /* Card 2: Soft Green */
    .card-2 {
      background: #f0fdf4;
      border-color: #dcfce7;
      color: #166534;
    }
    .card-2.active {
      border-color: #22c55e;
      background: #dcfce7;
    }
    .card-2 .step-badge {
      background: #bbf7d0;
      color: #15803d;
      border: 1px solid #16a34a;
    }

    /* Card 3: Vibrant Blue */
    .card-3 {
      background: #f0f9ff;
      border-color: #bae6fd;
      color: #0369a1;
    }
    .card-3.active {
      border-color: #0284c7;
      background: #e0f2fe;
    }
    .card-3 .step-badge {
      background: #0284c7;
      color: #ffffff;
      border: 1px solid #0369a1;
    }

    /* Controls Bar */
    .controls {
      display: flex;
      align-items: center;
      justify-content: center;
      gap: 8px;
      width: 100%;
      max-width: 420px;
      padding-top: 4px;
    }

    .nav-btn {
      background: #f1f5f9;
      border: 1px solid #cbd5e1;
      color: #334155;
      font-size: 14px;
      font-weight: 700;
      border-radius: 8px;
      padding: 6px 14px;
      cursor: pointer;
      transition: background 0.2s ease;
    }

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

    .step-dots {
      display: flex;
      gap: 6px;
      align-items: center;
      margin: 0 4px;
    }

    .dot {
      width: 10px;
      height: 10px;
      border-radius: 50%;
      background: #cbd5e1;
      cursor: pointer;
      transition: all 0.2s ease;
    }

    .dot.active {
      background: #0284c7;
      transform: scale(1.2);
    }
  </style>
</head>
<body>

  
  <div class="sequence-container">
    <div class="hops-row">
      <div class="hop-badge" id="hop1">+6</div>
      <div class="hop-badge" id="hop2">+6</div>
      <div class="hop-badge" id="hop3">+6</div>
      <div class="hop-badge" id="hop4">+6</div>
    </div>
    <div class="numbers-row">
      <div class="num-tile" id="tile0">5</div>
      <div class="num-tile" id="tile1">11</div>
      <div class="num-tile" id="tile2">17</div>
      <div class="num-tile" id="tile3">23</div>
      <div class="num-tile unknown" id="tile4">?</div>
    </div>
  </div>

  
  <div class="steps-list">
    <div class="step-card card-1 active" id="stepCard1" onclick="setStep(0)">
      <span class="step-badge">Step 1</span>
      <div class="step-content">
        <div class="step-title">Subtract neighbors</div>
        <div class="step-math">11 − 5 = <span style="font-weight:900">+6</span></div>
      </div>
    </div>

    <div class="step-card card-2" id="stepCard2" onclick="setStep(1)">
      <span class="step-badge">Step 2</span>
      <div class="step-content">
        <div class="step-title">Test next jump</div>
        <div class="step-math">17 − 11 = <span style="font-weight:900">+6</span> (Rule: +6 ✓)</div>
      </div>
    </div>

    <div class="step-card card-3" id="stepCard3" onclick="setStep(2)">
      <span class="step-badge">Step 3</span>
      <div class="step-content">
        <div class="step-title">Add to extend</div>
        <div class="step-math">23 + 6 = <span style="font-weight:900; color:#0284c7">29</span></div>
      </div>
    </div>
  </div>

  
  <div class="controls">
    <button class="nav-btn" onclick="prevStep()">← Prev</button>
    <button class="nav-btn" id="playBtn" onclick="togglePlay()">⏸</button>
    <button class="nav-btn" onclick="nextStep()">Next →</button>
    <div class="step-dots">
      <div class="dot active" onclick="setStep(0)"></div>
      <div class="dot" onclick="setStep(1)"></div>
      <div class="dot" onclick="setStep(2)"></div>
    </div>
  </div>

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

    const cards = [
      document.getElementById('stepCard1'),
      document.getElementById('stepCard2'),
      document.getElementById('stepCard3')
    ];

    const dots = document.querySelectorAll('.dot');
    const hops = [
      document.getElementById('hop1'),
      document.getElementById('hop2'),
      document.getElementById('hop3'),
      document.getElementById('hop4')
    ];

    const tiles = [
      document.getElementById('tile0'),
      document.getElementById('tile1'),
      document.getElementById('tile2'),
      document.getElementById('tile3'),
      document.getElementById('tile4')
    ];

    function render() {
      // Update cards & dots
      cards.forEach((card, idx) => {
        card.classList.toggle('active', idx === currentStep);
      });
      dots.forEach((dot, idx) => {
        dot.classList.toggle('active', idx === currentStep);
      });

      // Clear all tiles & hops
      tiles.forEach(t => {
        t.className = 'num-tile';
      });
      hops.forEach(h => {
        h.className = 'hop-badge';
      });

      if (currentStep === 0) {
        // Step 1: 11 - 5 = +6
        tiles[0].classList.add('highlight-yellow');
        tiles[1].classList.add('highlight-yellow');
        hops[0].classList.add('active-1');
        tiles[4].classList.add('unknown');
        tiles[4].textContent = '?';
      } else if (currentStep === 1) {
        // Step 2: 17 - 11 = +6, confirmed
        tiles[1].classList.add('highlight-green');
        tiles[2].classList.add('highlight-green');
        tiles[3].classList.add('highlight-green');
        hops[0].classList.add('active-2');
        hops[1].classList.add('active-2');
        hops[2].classList.add('active-2');
        tiles[4].classList.add('unknown');
        tiles[4].textContent = '?';
      } else if (currentStep === 2) {
        // Step 3: 23 + 6 = 29
        hops[0].classList.add('active-2');
        hops[1].classList.add('active-2');
        hops[2].classList.add('active-2');
        hops[3].classList.add('active-3');
        tiles[3].classList.add('highlight-green');
        tiles[4].classList.add('highlight-blue');
        tiles[4].textContent = '29';
      }
    }

    function setStep(idx) {
      currentStep = (idx + 3) % 3;
      render();
    }

    function nextStep() {
      setStep(currentStep + 1);
    }

    function prevStep() {
      setStep(currentStep - 1);
    }

    function togglePlay() {
      isPlaying = !isPlaying;
      document.getElementById('playBtn').textContent = isPlaying ? '⏸' : '▶';
      if (isPlaying) {
        startTimer();
      } else {
        clearInterval(timer);
      }
    }

    function startTimer() {
      clearInterval(timer);
      timer = setInterval(() => {
        nextStep();
      }, 3500);
    }

    render();
    startTimer();
  </script>
</body>
</html>

OGM.3.OA.8

Aligned learning resources

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