Identifying Prisms, Pyramids, Cylinders, and Cones

<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>Square Pyramid vs Rectangular Prism</title>
  <style>
    * {
      box-sizing: border-box;
      margin: 0;
      padding: 0;
    }

    body {
      font-family: system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
      background: transparent;
      color: #1e293b;
      padding: 12px 8px;
      display: flex;
      flex-direction: column;
      align-items: center;
      min-height: 100%;
      overflow-x: hidden;
    }

    .toolbar {
      display: flex;
      flex-wrap: wrap;
      justify-content: center;
      gap: 6px;
      margin-bottom: 12px;
      background: #f1f5f9;
      padding: 4px;
      border-radius: 20px;
    }

    .toggle-btn {
      border: none;
      background: transparent;
      padding: 6px 14px;
      font-size: 13px;
      font-weight: 600;
      color: #64748b;
      border-radius: 16px;
      cursor: pointer;
      transition: background-color 0.3s ease, color 0.3s ease;
    }

    .toggle-btn:hover {
      color: #1e293b;
      background-color: #e2e8f0;
    }

    .toggle-btn.active {
      background: #2563eb;
      color: #ffffff;
    }

    .shapes-grid {
      display: grid;
      grid-template-columns: repeat(2, minmax(0, 1fr));
      gap: 16px;
      width: 100%;
      max-width: 640px;
    }

    .shape-panel {
      display: flex;
      flex-direction: column;
      align-items: center;
      position: relative;
      min-width: 0;
      padding: 4px 0;
    }

    .shape-title {
      font-size: 15px;
      font-weight: 700;
      color: #0f172a;
      margin-bottom: 6px;
      text-align: center;
    }

    .svg-container {
      width: 100%;
      height: 165px;
      position: relative;
    }

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

    /* SVG Elements Styling */
    .face {
      transition: fill 0.3s ease, fill-opacity 0.3s ease;
      fill-opacity: 0.35;
    }

    .edge {
      stroke-width: 2;
      stroke-linecap: round;
      stroke-linejoin: round;
      transition: stroke 0.3s ease, stroke-width 0.3s ease, opacity 0.3s ease;
    }

    .edge.hidden {
      stroke-dasharray: 4 4;
      opacity: 0.55;
    }

    .vertex {
      transition: r 0.3s ease, fill 0.3s ease, stroke 0.3s ease;
    }

    /* Active Highlight States */
    .hl-faces .face {
      fill: #3b82f6 !important;
      fill-opacity: 0.65 !important;
    }
    .hl-faces .face.base {
      fill: #10b981 !important;
      fill-opacity: 0.75 !important;
    }

    .hl-edges .edge {
      stroke: #d97706 !important;
      stroke-width: 3.5 !important;
      opacity: 1 !important;
    }

    .hl-vertices .vertex {
      r: 6 !important;
      fill: #ef4444 !important;
      stroke: #ffffff;
      stroke-width: 2;
    }

    /* Apex Indicator Animation - Gentle and non-flickering */
    .apex-arrow {
      animation: apexBob 2.5s ease-in-out infinite;
    }

    @keyframes apexBob {
      0%, 100% {
        transform: translateY(0);
      }
      50% {
        transform: translateY(-4px);
      }
    }

    /* Formula & Count Badges */
    .stats-panel {
      display: flex;
      flex-direction: column;
      gap: 5px;
      width: 100%;
      margin-top: 8px;
    }

    .stat-row {
      display: flex;
      justify-content: space-between;
      align-items: center;
      background: #f8fafc;
      border: 1px solid #e2e8f0;
      border-radius: 6px;
      padding: 5px 8px;
      font-size: 12px;
      font-weight: 600;
      color: #475569;
      gap: 6px;
      transition: background-color 0.3s ease, border-color 0.3s ease, color 0.3s ease;
    }

    .stat-row.highlight {
      background: #eff6ff;
      border-color: #93c5fd;
      color: #1e40af;
    }

    .stat-label {
      white-space: nowrap;
    }

    .stat-val {
      font-weight: 700;
      font-variant-numeric: tabular-nums;
      text-align: right;
    }

    .formula {
      font-size: 11px;
      color: #7c3aed;
      font-weight: 700;
      background: #f3e8ff;
      padding: 1px 4px;
      border-radius: 4px;
    }

    @media (max-width: 500px) {
      .shapes-grid {
        grid-template-columns: 1fr;
        gap: 16px;
      }

      .svg-container {
        height: 150px;
      }

      .stat-row {
        padding: 4px 7px;
        font-size: 11.5px;
      }

      .toggle-btn {
        padding: 5px 11px;
        font-size: 12px;
      }
    }
  </style>
</head>
<body>

  
  <div class="toolbar" role="tablist" aria-label="Highlight Mode Selector">
    <button class="toggle-btn active" data-mode="all" role="tab" aria-selected="true">Show All</button>
    <button class="toggle-btn" data-mode="faces" role="tab" aria-selected="false">Faces</button>
    <button class="toggle-btn" data-mode="vertices" role="tab" aria-selected="false">Vertices</button>
    <button class="toggle-btn" data-mode="edges" role="tab" aria-selected="false">Edges</button>
  </div>

  
  <div class="shapes-grid" id="shapesGrid">
    
    
    <div class="shape-panel" id="panelPyramid">
      <div class="shape-title">Square Pyramid</div>
      <div class="svg-container">
        <svg viewBox="0 0 200 175" preserveAspectRatio="xMidYMid meet">
          <defs>
            <marker id="arrow" viewBox="0 0 10 10" refX="5" refY="5" markerWidth="4" markerHeight="4" orient="auto-start-reverse">
              <path d="M 0 1.5 L 8 5 L 0 8.5 z" fill="#2563eb"/>
            </marker>
          </defs>

          
          <polygon class="face base" points="40,138 100,158 160,138 100,122" fill="#10b981" />
          <line class="edge hidden" x1="40" y1="138" x2="100" y2="122" stroke="#94a3b8" />
          <line class="edge hidden" x1="100" y1="122" x2="160" y2="138" stroke="#94a3b8" />
          <line class="edge hidden" x1="100" y1="48" x2="100" y2="122" stroke="#94a3b8" />

          
          <polygon class="face" points="100,48 40,138 100,158" fill="#60a5fa" />
          <polygon class="face" points="100,48 100,158 160,138" fill="#93c5fd" />

          
          <line class="edge" x1="40" y1="138" x2="100" y2="158" stroke="#334155" />
          <line class="edge" x1="100" y1="158" x2="160" y2="138" stroke="#334155" />
          <line class="edge" x1="100" y1="48" x2="40" y2="138" stroke="#334155" />
          <line class="edge" x1="100" y1="48" x2="100" y2="158" stroke="#334155" />
          <line class="edge" x1="100" y1="48" x2="160" y2="138" stroke="#334155" />

          
          <circle class="vertex" cx="100" cy="122" r="3.5" fill="#64748b" />
          <circle class="vertex" cx="40" cy="138" r="3.5" fill="#64748b" />
          <circle class="vertex" cx="100" cy="158" r="3.5" fill="#64748b" />
          <circle class="vertex" cx="160" cy="138" r="3.5" fill="#64748b" />

          
          <circle class="vertex" cx="100" cy="48" r="4.5" fill="#2563eb" />

          
          <g class="apex-arrow">
            <text x="100" y="18" text-anchor="middle" font-size="12" font-weight="700" fill="#2563eb">Apex</text>
            <line x1="100" y1="23" x2="100" y2="40" stroke="#2563eb" stroke-width="2" marker-end="url(#arrow)" />
          </g>
        </svg>
      </div>

      <div class="stats-panel">
        <div class="stat-row" data-kind="faces">
          <span class="stat-label">Faces: <span class="formula">n + 1</span></span>
          <span class="stat-val">5 (4▲ + 1■)</span>
        </div>
        <div class="stat-row" data-kind="vertices">
          <span class="stat-label">Vertices: <span class="formula">n + 1</span></span>
          <span class="stat-val">5 (4 base + 1 apex)</span>
        </div>
        <div class="stat-row" data-kind="edges">
          <span class="stat-label">Edges: <span class="formula">2n</span></span>
          <span class="stat-val">8 (4 base + 4 lateral)</span>
        </div>
      </div>
    </div>

    
    <div class="shape-panel" id="panelPrism">
      <div class="shape-title">Rectangular Prism</div>
      <div class="svg-container">
        <svg viewBox="0 0 200 175" preserveAspectRatio="xMidYMid meet">
          
          <polygon class="face base" points="40,138 100,158 160,138 100,122" fill="#10b981" />
          <line class="edge hidden" x1="40" y1="138" x2="100" y2="122" stroke="#94a3b8" />
          <line class="edge hidden" x1="100" y1="122" x2="160" y2="138" stroke="#94a3b8" />
          <line class="edge hidden" x1="100" y1="54" x2="100" y2="122" stroke="#94a3b8" />

          
          <polygon class="face" points="40,70 100,90 100,158 40,138" fill="#60a5fa" />
          <polygon class="face" points="100,90 160,70 160,138 100,158" fill="#93c5fd" />
          <polygon class="face base" points="40,70 100,90 160,70 100,54" fill="#34d399" />

          
          <line class="edge" x1="40" y1="138" x2="100" y2="158" stroke="#334155" />
          <line class="edge" x1="100" y1="158" x2="160" y2="138" stroke="#334155" />
          <line class="edge" x1="40" y1="70" x2="100" y2="90" stroke="#334155" />
          <line class="edge" x1="100" y1="90" x2="160" y2="70" stroke="#334155" />
          <line class="edge" x1="160" y1="70" x2="100" y2="54" stroke="#334155" />
          <line class="edge" x1="100" y1="54" x2="40" y2="70" stroke="#334155" />
          <line class="edge" x1="40" y1="70" x2="40" y2="138" stroke="#334155" />
          <line class="edge" x1="100" y1="90" x2="100" y2="158" stroke="#334155" />
          <line class="edge" x1="160" y1="70" x2="160" y2="138" stroke="#334155" />

          
          <circle class="vertex" cx="100" cy="122" r="3.5" fill="#64748b" />
          <circle class="vertex" cx="40" cy="138" r="3.5" fill="#64748b" />
          <circle class="vertex" cx="100" cy="158" r="3.5" fill="#64748b" />
          <circle class="vertex" cx="160" cy="138" r="3.5" fill="#64748b" />
          <circle class="vertex" cx="100" cy="54" r="3.5" fill="#64748b" />
          <circle class="vertex" cx="40" cy="70" r="3.5" fill="#64748b" />
          <circle class="vertex" cx="100" cy="90" r="3.5" fill="#64748b" />
          <circle class="vertex" cx="160" cy="70" r="3.5" fill="#64748b" />
        </svg>
      </div>

      <div class="stats-panel">
        <div class="stat-row" data-kind="faces">
          <span class="stat-label">Faces: <span class="formula">n + 2</span></span>
          <span class="stat-val">6 (4 sides + 2 bases)</span>
        </div>
        <div class="stat-row" data-kind="vertices">
          <span class="stat-label">Vertices: <span class="formula">2n</span></span>
          <span class="stat-val">8 (4 top + 4 bottom)</span>
        </div>
        <div class="stat-row" data-kind="edges">
          <span class="stat-label">Edges: <span class="formula">3n</span></span>
          <span class="stat-val">12 (4 top + 4 bot + 4 vert)</span>
        </div>
      </div>
    </div>

  </div>

  <script>
    const buttons = document.querySelectorAll('.toggle-btn');
    const grid = document.getElementById('shapesGrid');
    const statRows = document.querySelectorAll('.stat-row');

    buttons.forEach(btn => {
      btn.addEventListener('click', () => {
        buttons.forEach(b => {
          b.classList.remove('active');
          b.setAttribute('aria-selected', 'false');
        });
        btn.classList.add('active');
        btn.setAttribute('aria-selected', 'true');

        const mode = btn.dataset.mode;
        grid.className = 'shapes-grid' + (mode !== 'all' ? ' hl-' + mode : '');

        statRows.forEach(row => {
          if (mode === 'all') {
            row.classList.remove('highlight');
          } else if (row.dataset.kind === mode) {
            row.classList.add('highlight');
          } else {
            row.classList.remove('highlight');
          }
        });
      });
    });
  </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>Cylinder vs Cone</title>
  <style>
    * { box-sizing: border-box; margin: 0; padding: 0; }
    body {
      font-family: system-ui, -apple-system, sans-serif;
      color: #1e293b;
      background: #ffffff;
      padding: 8px;
      display: flex;
      flex-direction: column;
      align-items: center;
      justify-content: center;
      min-height: 100%;
      user-select: none;
    }

    .controls {
      display: flex;
      flex-wrap: wrap;
      gap: 6px;
      justify-content: center;
      margin-bottom: 8px;
      width: 100%;
      max-width: 540px;
    }

    .btn-group {
      display: flex;
      background: #f1f5f9;
      padding: 3px;
      border-radius: 8px;
      gap: 2px;
    }

    .tab-btn, .filter-btn {
      border: none;
      background: transparent;
      padding: 5px 10px;
      font-size: 13px;
      font-weight: 600;
      color: #64748b;
      border-radius: 6px;
      cursor: pointer;
      transition: all 0.2s ease;
    }

    .tab-btn.active, .filter-btn.active {
      background: #ffffff;
      color: #0f172a;
      box-shadow: 0 1px 3px rgba(0,0,0,0.1);
    }

    .stage {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 12px;
      width: 100%;
      max-width: 540px;
    }

    .shape-card {
      background: #f8fafc;
      border: 1px solid #e2e8f0;
      border-radius: 12px;
      padding: 10px;
      display: flex;
      flex-direction: column;
      align-items: center;
      position: relative;
    }

    .shape-title {
      font-size: 15px;
      font-weight: 700;
      color: #0f172a;
      margin-bottom: 4px;
    }

    .svg-wrap {
      width: 100%;
      height: 180px;
      display: flex;
      align-items: center;
      justify-content: center;
    }

    svg {
      width: 100%;
      height: 100%;
      overflow: visible;
    }

    /* Shape stylings & transitions */
    .part-face {
      fill: #38bdf8;
      stroke: #0284c7;
      stroke-width: 2;
      transition: all 0.3s ease;
    }
    .part-wall {
      fill: #fbbf24;
      stroke: #d97706;
      stroke-width: 2;
      transition: all 0.3s ease;
    }
    .part-apex {
      fill: #f43f5e;
      stroke: #ffffff;
      stroke-width: 2.5;
      transition: all 0.3s ease;
    }

    .dimmed {
      opacity: 0.15 !important;
    }
    .highlight {
      filter: drop-shadow(0 0 6px rgba(14, 165, 233, 0.6));
    }
    .highlight-apex {
      filter: drop-shadow(0 0 8px rgba(244, 63, 94, 0.9));
      animation: pulse 1.2s infinite alternate ease-in-out;
    }

    @keyframes pulse {
      from { transform: scale(1); }
      to { transform: scale(1.4); }
    }

    .stats {
      display: flex;
      gap: 4px;
      flex-wrap: wrap;
      justify-content: center;
      margin-top: 6px;
      width: 100%;
    }

    .tag {
      font-size: 11px;
      font-weight: 600;
      padding: 3px 6px;
      border-radius: 4px;
      background: #ffffff;
      border: 1px solid #cbd5e1;
      color: #475569;
      transition: all 0.2s ease;
    }

    .tag.active-tag {
      border-color: currentColor;
      font-weight: 700;
      transform: translateY(-1px);
    }
    .tag-blue { color: #0284c7; }
    .tag-amber { color: #d97706; }
    .tag-rose { color: #e11d48; }

    @media (max-width: 380px) {
      .shape-title { font-size: 13px; }
      .svg-wrap { height: 150px; }
      .tag { font-size: 10px; padding: 2px 4px; }
    }
  </style>
</head>
<body>

  
  <div class="controls">
    <div class="btn-group">
      <button class="tab-btn active" id="tab3D" onclick="setView('3d')">3D Solid</button>
      <button class="tab-btn" id="tabNet" onclick="setView('net')">Unrolled Net</button>
    </div>
    <div class="btn-group">
      <button class="filter-btn active" id="fAll" onclick="setFilter('all')">All</button>
      <button class="filter-btn" id="fFaces" onclick="setFilter('faces')">Flat Bases</button>
      <button class="filter-btn" id="fWall" onclick="setFilter('wall')">Curved Wall</button>
      <button class="filter-btn" id="fApex" onclick="setFilter('apex')">Apex</button>
    </div>
  </div>

  
  <div class="stage">
    
    <div class="shape-card">
      <div class="shape-title">Cylinder</div>
      <div class="svg-wrap">
        <svg viewBox="0 0 160 180" id="svgCylinder">
          
          <g id="cyl3D">
            
            <path class="part-wall" d="M 35 48 L 35 132 A 45 14 0 0 0 125 132 L 125 48 Z" fill-opacity="0.85"/>
            
            <path d="M 35 132 A 45 14 0 0 1 125 132" fill="none" stroke="#0284c7" stroke-width="1.5" stroke-dasharray="3,3"/>
            
            <path class="part-face" d="M 35 132 A 45 14 0 0 0 125 132 A 45 14 0 0 1 35 132" fill-opacity="0.9"/>
            
            <ellipse class="part-face" cx="80" cy="48" rx="45" ry="14" fill-opacity="0.95"/>
          </g>

          
          <g id="cylNet" style="display: none;">
            
            <circle class="part-face" cx="80" cy="26" r="20" fill-opacity="0.95"/>
            
            <rect class="part-wall" x="22" y="52" width="116" height="76" rx="2" fill-opacity="0.85"/>
            
            <circle class="part-face" cx="80" cy="154" r="20" fill-opacity="0.95"/>
          </g>
        </svg>
      </div>
      
      <div class="stats" id="cylStats">
        <span class="tag tag-blue" id="tagCylFaces">2 Flat Faces</span>
        <span class="tag tag-amber" id="tagCylWall">1 Curved Wall</span>
        <span class="tag" id="tagCylApex">0 Vertices</span>
      </div>
    </div>

    
    <div class="shape-card">
      <div class="shape-title">Cone</div>
      <div class="svg-wrap">
        <svg viewBox="0 0 160 180" id="svgCone">
          
          <g id="cone3D">
            
            <path class="part-wall" d="M 80 32 L 35 132 A 45 14 0 0 0 125 132 Z" fill-opacity="0.85"/>
            
            <path d="M 35 132 A 45 14 0 0 1 125 132" fill="none" stroke="#0284c7" stroke-width="1.5" stroke-dasharray="3,3"/>
            
            <path class="part-face" d="M 35 132 A 45 14 0 0 0 125 132 A 45 14 0 0 1 35 132" fill-opacity="0.9"/>
            
            <g id="apexGroup" style="transform-origin: 80px 32px;">
              <circle class="part-apex" cx="80" cy="32" r="5.5"/>
            </g>
          </g>

          
          <g id="coneNet" style="display: none;">
            
            <path class="part-wall" d="M 80 20 L 22 105 A 105 105 0 0 0 138 105 Z" fill-opacity="0.85"/>
            
            <circle class="part-face" cx="80" cy="148" r="22" fill-opacity="0.95"/>
            
            <g id="apexNetGroup" style="transform-origin: 80px 20px;">
              <circle class="part-apex" cx="80" cy="20" r="5"/>
            </g>
          </g>
        </svg>
      </div>
      
      <div class="stats" id="coneStats">
        <span class="tag tag-rose" id="tagConeApex">1 Apex</span>
        <span class="tag tag-blue" id="tagConeFace">1 Flat Face</span>
        <span class="tag tag-amber" id="tagConeWall">1 Curved Wall</span>
      </div>
    </div>
  </div>

  <script>
    let currentView = '3d';
    let currentFilter = 'all';

    function setView(view) {
      currentView = view;
      document.getElementById('tab3D').classList.toggle('active', view === '3d');
      document.getElementById('tabNet').classList.toggle('active', view === 'net');

      document.getElementById('cyl3D').style.display = view === '3d' ? 'inline' : 'none';
      document.getElementById('cylNet').style.display = view === 'net' ? 'inline' : 'none';
      document.getElementById('cone3D').style.display = view === '3d' ? 'inline' : 'none';
      document.getElementById('coneNet').style.display = view === 'net' ? 'inline' : 'none';

      // Update labels to reflect 3D vs Net context
      if (view === 'net') {
        document.getElementById('tagCylWall').textContent = 'Rectangle';
        document.getElementById('tagConeWall').textContent = 'Sector';
        document.getElementById('tagCylFaces').textContent = '2 Circles';
        document.getElementById('tagConeFace').textContent = '1 Circle';
      } else {
        document.getElementById('tagCylWall').textContent = '1 Curved Wall';
        document.getElementById('tagConeWall').textContent = '1 Curved Wall';
        document.getElementById('tagCylFaces').textContent = '2 Flat Faces';
        document.getElementById('tagConeFace').textContent = '1 Flat Face';
      }

      applyHighlights();
    }

    function setFilter(filter) {
      currentFilter = filter;
      document.querySelectorAll('.filter-btn').forEach(btn => btn.classList.remove('active'));
      const activeBtn = {
        'all': 'fAll',
        'faces': 'fFaces',
        'wall': 'fWall',
        'apex': 'fApex'
      }[filter];
      if (activeBtn) document.getElementById(activeBtn).classList.add('active');

      applyHighlights();
    }

    function applyHighlights() {
      const faces = document.querySelectorAll('.part-face');
      const walls = document.querySelectorAll('.part-wall');
      const apexes = document.querySelectorAll('.part-apex');

      faces.forEach(el => {
        el.classList.toggle('dimmed', currentFilter !== 'all' && currentFilter !== 'faces');
        el.classList.toggle('highlight', currentFilter === 'faces');
      });

      walls.forEach(el => {
        el.classList.toggle('dimmed', currentFilter !== 'all' && currentFilter !== 'wall');
        el.classList.toggle('highlight', currentFilter === 'wall');
      });

      apexes.forEach(el => {
        el.classList.toggle('dimmed', currentFilter !== 'all' && currentFilter !== 'apex');
        el.classList.toggle('highlight-apex', currentFilter === 'apex');
      });

      // Tags styling
      document.getElementById('tagCylFaces').classList.toggle('active-tag', currentFilter === 'faces');
      document.getElementById('tagConeFace').classList.toggle('active-tag', currentFilter === 'faces');
      document.getElementById('tagCylWall').classList.toggle('active-tag', currentFilter === 'wall');
      document.getElementById('tagConeWall').classList.toggle('active-tag', currentFilter === 'wall');
      document.getElementById('tagConeApex').classList.toggle('active-tag', currentFilter === 'apex');
      document.getElementById('tagCylApex').classList.toggle('active-tag', currentFilter === 'apex');
    }
  </script>
</body>
</html>

<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <style>
    * { box-sizing: border-box; margin: 0; padding: 0; }
    body {
      font-family: system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
      background: #f8fafc;
      color: #1e293b;
      padding: 10px;
      display: flex;
      flex-direction: column;
      align-items: center;
      min-height: 100%;
      user-select: none;
      -webkit-user-select: none;
    }
    .layout {
      width: 100%;
      max-width: 540px;
      display: flex;
      flex-direction: column;
      gap: 10px;
    }
    .top-bar {
      display: flex;
      flex-wrap: wrap;
      justify-content: space-between;
      align-items: center;
      gap: 6px;
    }
    .pill-group {
      display: flex;
      gap: 6px;
      flex-wrap: wrap;
    }
    .nav-btn {
      background: #e2e8f0;
      border: 1px solid #cbd5e1;
      border-radius: 16px;
      padding: 5px 12px;
      font-size: 13px;
      font-weight: 600;
      color: #475569;
      cursor: pointer;
      transition: background 0.2s, color 0.2s, border-color 0.2s;
    }
    .nav-btn.active {
      background: #2563eb;
      border-color: #2563eb;
      color: #ffffff;
    }
    .drag-hint {
      font-size: 12px;
      color: #64748b;
      font-weight: 600;
      display: flex;
      align-items: center;
      gap: 4px;
    }
    .view-card {
      position: relative;
      width: 100%;
      height: 190px;
      background: #ffffff;
      border: 1px solid #e2e8f0;
      border-radius: 12px;
      overflow: hidden;
      display: flex;
      align-items: center;
      justify-content: center;
      touch-action: none;
    }
    canvas {
      width: 100%;
      height: 100%;
      display: block;
      cursor: grab;
    }
    canvas:active {
      cursor: grabbing;
    }
    .badge {
      position: absolute;
      bottom: 8px;
      right: 8px;
      padding: 4px 10px;
      border-radius: 20px;
      font-size: 12px;
      font-weight: 700;
      background: rgba(241, 245, 249, 0.9);
      color: #475569;
      border: 1px solid #cbd5e1;
      display: flex;
      align-items: center;
      gap: 4px;
      pointer-events: none;
      transition: background 0.3s, color 0.3s, border-color 0.3s;
    }
    .badge.solved {
      background: #22c55e;
      border-color: #16a34a;
      color: #ffffff;
    }
    .hints-row {
      display: grid;
      grid-template-columns: 1fr 1fr 1fr;
      gap: 6px;
    }
    .clue-box {
      background: #ffffff;
      border: 1px solid #e2e8f0;
      border-radius: 8px;
      padding: 6px;
      display: flex;
      flex-direction: column;
      gap: 4px;
    }
    .clue-label {
      font-size: 11px;
      font-weight: 700;
      text-transform: uppercase;
      letter-spacing: 0.5px;
      color: #64748b;
      text-align: center;
      white-space: nowrap;
    }
    .choice-group {
      display: flex;
      flex-direction: column;
      gap: 4px;
    }
    .choice-btn {
      border: 1px solid #cbd5e1;
      background: #f8fafc;
      border-radius: 6px;
      padding: 5px 2px;
      font-size: 11px;
      font-weight: 600;
      color: #334155;
      cursor: pointer;
      text-align: center;
      transition: background 0.15s, border-color 0.15s, color 0.15s;
    }
    .choice-btn:focus-visible {
      outline: 2px solid #2563eb;
    }
    .choice-btn.selected {
      background: #2563eb;
      border-color: #2563eb;
      color: #ffffff;
    }
    .choice-btn.correct-choice {
      background: #16a34a;
      border-color: #15803d;
      color: #ffffff;
    }
    .choice-btn.wrong-choice {
      background: #fee2e2;
      border-color: #ef4444;
      color: #dc2626;
    }
    .status-banner {
      min-height: 32px;
      border-radius: 8px;
      display: flex;
      align-items: center;
      justify-content: center;
      font-size: 13px;
      font-weight: 600;
      text-align: center;
      padding: 6px 10px;
      background: #f1f5f9;
      color: #475569;
      border: 1px solid #e2e8f0;
    }
    .status-banner.success {
      background: #dcfce7;
      border-color: #86efac;
      color: #15803d;
    }
    @media (max-width: 380px) {
      .pill-group {
        gap: 4px;
      }
      .nav-btn {
        padding: 4px 8px;
        font-size: 12px;
      }
      .choice-btn {
        font-size: 10px;
        padding: 4px 1px;
      }
      .clue-label {
        font-size: 10px;
      }
      .drag-hint {
        font-size: 11px;
      }
    }
  </style>
</head>
<body>
  <div class="layout">
    <div class="top-bar">
      <div class="pill-group" id="solidTabs">
        <button class="nav-btn active" data-idx="0">Solid 1</button>
        <button class="nav-btn" data-idx="1">Solid 2</button>
        <button class="nav-btn" data-idx="2">Solid 3</button>
        <button class="nav-btn" data-idx="3">Solid 4</button>
      </div>
      <span class="drag-hint">🔄 Drag to rotate</span>
    </div>

    <div class="view-card">
      <canvas id="wire-canvas"></canvas>
      <div class="badge" id="badge">🔍 Detective Mode</div>
    </div>

    <div class="hints-row">
      <div class="clue-box" data-q="surfaces">
        <div class="clue-label">1. Surfaces</div>
        <div class="choice-group">
          <button class="choice-btn" data-val="flat">All Flat</button>
          <button class="choice-btn" data-val="curved">Has Curved</button>
        </div>
      </div>

      <div class="clue-box" data-q="bases">
        <div class="clue-label">2. Bases</div>
        <div class="choice-group">
          <button class="choice-btn" data-val="1">1 Base (Apex)</button>
          <button class="choice-btn" data-val="2">2 Parallel Bases</button>
        </div>
      </div>

      <div class="clue-box" data-q="shape">
        <div class="clue-label">3. Base Shape</div>
        <div class="choice-group">
          <button class="choice-btn" data-val="circle">Circle</button>
          <button class="choice-btn" data-val="polygon">Polygon</button>
        </div>
      </div>
    </div>

    <div class="status-banner" id="statusBanner">
      Identify all 3 clues to classify the solid!
    </div>
  </div>

  <script>
    // 3D Geometry generator without external libraries
    function createCylinderModel() {
      const segs = 24;
      const r = 1.0;
      const h = 2.0;
      const vertices = [];
      const edges = [];
      const faces = [];

      // Top vertices: 0 .. segs-1
      // Bottom vertices: segs .. 2*segs-1
      for (let i = 0; i < segs; i++) {
        const theta = (i / segs) * Math.PI * 2;
        vertices.push([r * Math.cos(theta), h / 2, r * Math.sin(theta)]);
      }
      for (let i = 0; i < segs; i++) {
        const theta = (i / segs) * Math.PI * 2;
        vertices.push([r * Math.cos(theta), -h / 2, r * Math.sin(theta)]);
      }

      const topFace = [];
      const botFace = [];
      for (let i = 0; i < segs; i++) {
        const next = (i + 1) % segs;
        topFace.push(i);
        botFace.unshift(segs + i);
        edges.push([i, next]);
        edges.push([segs + i, segs + next]);
        if (i % 3 === 0) {
          edges.push([i, segs + i]);
        }
        faces.push({ indices: [i, next, segs + next, segs + i], color: '56, 189, 248' });
      }
      faces.push({ indices: topFace, color: '14, 165, 233' });
      faces.push({ indices: botFace, color: '14, 165, 233' });

      return { vertices, edges, faces, edgeColor: '#0284c7' };
    }

    function createSquarePyramidModel() {
      const w = 1.25;
      const h = 2.0;
      const vertices = [
        [0, h / 2, 0], // apex 0
        [-w, -h / 2, -w], // 1
        [w, -h / 2, -w],  // 2
        [w, -h / 2, w],   // 3
        [-w, -h / 2, w]   // 4
      ];
      const edges = [
        [0, 1], [0, 2], [0, 3], [0, 4],
        [1, 2], [2, 3], [3, 4], [4, 1]
      ];
      const faces = [
        { indices: [0, 1, 2], color: '251, 191, 36' },
        { indices: [0, 2, 3], color: '245, 158, 11' },
        { indices: [0, 3, 4], color: '251, 191, 36' },
        { indices: [0, 4, 1], color: '245, 158, 11' },
        { indices: [4, 3, 2, 1], color: '217, 119, 6' }
      ];
      return { vertices, edges, faces, edgeColor: '#b45309' };
    }

    function createConeModel() {
      const segs = 24;
      const r = 1.15;
      const h = 2.1;
      const vertices = [[0, h / 2, 0]]; // 0 = apex
      const edges = [];
      const faces = [];

      for (let i = 0; i < segs; i++) {
        const theta = (i / segs) * Math.PI * 2;
        vertices.push([r * Math.cos(theta), -h / 2, r * Math.sin(theta)]);
      }

      const botFace = [];
      for (let i = 1; i <= segs; i++) {
        const next = i === segs ? 1 : i + 1;
        edges.push([i, next]);
        if ((i - 1) % 3 === 0) {
          edges.push([0, i]);
        }
        faces.push({ indices: [0, next, i], color: '167, 139, 250' });
        botFace.unshift(i);
      }
      faces.push({ indices: botFace, color: '139, 92, 246' });

      return { vertices, edges, faces, edgeColor: '#6d28d9' };
    }

    function createPrismModel() {
      const w = 1.3, h = 1.8, d = 1.1;
      const vertices = [
        [-w / 2, h / 2, -d / 2], // 0
        [w / 2, h / 2, -d / 2],  // 1
        [w / 2, h / 2, d / 2],   // 2
        [-w / 2, h / 2, d / 2],  // 3
        [-w / 2, -h / 2, -d / 2],// 4
        [w / 2, -h / 2, -d / 2], // 5
        [w / 2, -h / 2, d / 2],  // 6
        [-w / 2, -h / 2, d / 2]  // 7
      ];
      const edges = [
        [0, 1], [1, 2], [2, 3], [3, 0],
        [4, 5], [5, 6], [6, 7], [7, 4],
        [0, 4], [1, 5], [2, 6], [3, 7]
      ];
      const faces = [
        { indices: [0, 1, 2, 3], color: '52, 211, 153' }, // Top
        { indices: [7, 6, 5, 4], color: '16, 185, 129' }, // Bottom
        { indices: [0, 4, 5, 1], color: '52, 211, 153' }, // Back
        { indices: [3, 2, 6, 7], color: '16, 185, 129' }, // Front
        { indices: [0, 3, 7, 4], color: '5, 150, 105' },  // Left
        { indices: [1, 5, 6, 2], color: '52, 211, 153' }  // Right
      ];
      return { vertices, edges, faces, edgeColor: '#047857' };
    }

    const solids = [
      {
        name: 'Cylinder',
        surfaces: 'curved',
        bases: '2',
        shape: 'circle',
        model: createCylinderModel()
      },
      {
        name: 'Square Pyramid',
        surfaces: 'flat',
        bases: '1',
        shape: 'polygon',
        model: createSquarePyramidModel()
      },
      {
        name: 'Cone',
        surfaces: 'curved',
        bases: '1',
        shape: 'circle',
        model: createConeModel()
      },
      {
        name: 'Rectangular Prism',
        surfaces: 'flat',
        bases: '2',
        shape: 'polygon',
        model: createPrismModel()
      }
    ];

    let currentIdx = 0;
    let userAnswers = { surfaces: null, bases: null, shape: null };

    // Canvas 3D rendering setup
    const canvas = document.getElementById('wire-canvas');
    const ctx = canvas.getContext('2d');

    let rotX = 0.35;
    let rotY = 0.55;
    let isDragging = false;
    let lastMousePos = { x: 0, y: 0 };
    let dpr = window.devicePixelRatio || 1;

    function resizeCanvas() {
      const rect = canvas.getBoundingClientRect();
      dpr = window.devicePixelRatio || 1;
      canvas.width = rect.width * dpr;
      canvas.height = rect.height * dpr;
    }
    window.addEventListener('resize', resizeCanvas);
    resizeCanvas();

    function rotateVertex(v, rx, ry) {
      // Rotate around Y
      const cosY = Math.cos(ry);
      const sinY = Math.sin(ry);
      const x1 = v[0] * cosY + v[2] * sinY;
      const y1 = v[1];
      const z1 = -v[0] * sinY + v[2] * cosY;

      // Rotate around X
      const cosX = Math.cos(rx);
      const sinX = Math.sin(rx);
      const x2 = x1;
      const y2 = y1 * cosX - z1 * sinX;
      const z2 = y1 * sinX + z1 * cosX;

      return [x2, y2, z2];
    }

    function project(v, w, h) {
      const cameraDist = 4.2;
      const scale = Math.min(w, h) * 0.95;
      const fov = scale / (cameraDist + v[2]);
      return {
        x: w / 2 + v[0] * fov,
        y: h / 2 - v[1] * fov,
        z: v[2]
      };
    }

    function render() {
      if (!isDragging) {
        rotY += 0.008;
      }

      const w = canvas.width;
      const h = canvas.height;
      ctx.clearRect(0, 0, w, h);

      const model = solids[currentIdx].model;
      const rotated = model.vertices.map(v => rotateVertex(v, rotX, rotY));
      const projected = rotated.map(v => project(v, w, h));

      // Calculate faces depth & normals
      const faceList = model.faces.map(face => {
        let avgZ = 0;
        face.indices.forEach(idx => { avgZ += rotated[idx][2]; });
        avgZ /= face.indices.length;

        // Normal computation from first 3 vertices
        const p0 = rotated[face.indices[0]];
        const p1 = rotated[face.indices[1]];
        const p2 = rotated[face.indices[2]];
        const vA = [p1[0] - p0[0], p1[1] - p0[1], p1[2] - p0[2]];
        const vB = [p2[0] - p0[0], p2[1] - p0[1], p2[2] - p0[2]];
        const nx = vA[1] * vB[2] - vA[2] * vB[1];
        const ny = vA[2] * vB[0] - vA[0] * vB[2];
        const nz = vA[0] * vB[1] - vA[1] * vB[0];
        const len = Math.hypot(nx, ny, nz) || 1;

        // Directional light vector [0.5, 0.7, 1.0] normalized
        const l = [0.408, 0.571, 0.714];
        const dot = Math.max(0.15, (nx / len) * l[0] + (ny / len) * l[1] + (nz / len) * l[2]);

        return {
          face,
          avgZ,
          shade: dot
        };
      });

      // Painter's algorithm sort
      faceList.sort((a, b) => a.avgZ - b.avgZ);

      // Draw shaded faces with semi-transparency
      faceList.forEach(item => {
        const poly = item.face.indices.map(i => projected[i]);
        ctx.beginPath();
        ctx.moveTo(poly[0].x, poly[0].y);
        for (let i = 1; i < poly.length; i++) {
          ctx.lineTo(poly[i].x, poly[i].y);
        }
        ctx.closePath();
        const alpha = 0.55 + item.shade * 0.25;
        ctx.fillStyle = `rgba(${item.face.color}, ${alpha.toFixed(2)})`;
        ctx.fill();
      });

      // Draw wireframe edges
      ctx.lineWidth = 1.8 * dpr;
      ctx.strokeStyle = model.edgeColor;
      ctx.lineJoin = 'round';
      ctx.lineCap = 'round';

      model.edges.forEach(edge => {
        const p1 = projected[edge[0]];
        const p2 = projected[edge[1]];
        ctx.beginPath();
        ctx.moveTo(p1.x, p1.y);
        ctx.lineTo(p2.x, p2.y);
        ctx.stroke();
      });

      // Small vertex points for crisp geometry feel
      ctx.fillStyle = model.edgeColor;
      projected.forEach(p => {
        ctx.beginPath();
        ctx.arc(p.x, p.y, 2 * dpr, 0, Math.PI * 2);
        ctx.fill();
      });

      requestAnimationFrame(render);
    }
    requestAnimationFrame(render);

    // Pointer events for smooth drag interaction
    canvas.parentElement.addEventListener('pointerdown', (e) => {
      isDragging = true;
      lastMousePos = { x: e.clientX, y: e.clientY };
      canvas.setPointerCapture(e.pointerId);
    });

    window.addEventListener('pointermove', (e) => {
      if (!isDragging) return;
      const dx = e.clientX - lastMousePos.x;
      const dy = e.clientY - lastMousePos.y;
      rotY += dx * 0.012;
      rotX += dy * 0.012;
      // Clamp vertical rotation
      rotX = Math.max(-1.4, Math.min(1.4, rotX));
      lastMousePos = { x: e.clientX, y: e.clientY };
    });

    window.addEventListener('pointerup', () => { isDragging = false; });
    window.addEventListener('pointercancel', () => { isDragging = false; });

    // Detective UI Logic
    const badge = document.getElementById('badge');
    const banner = document.getElementById('statusBanner');
    const tabs = document.querySelectorAll('.nav-btn');
    const clueButtons = document.querySelectorAll('.choice-btn');

    function loadSolid(idx) {
      currentIdx = idx;
      userAnswers = { surfaces: null, bases: null, shape: null };
      updateUI();
    }

    tabs.forEach((tab) => {
      tab.addEventListener('click', () => {
        tabs.forEach(t => t.classList.remove('active'));
        tab.classList.add('active');
        loadSolid(parseInt(tab.dataset.idx, 10));
      });
    });

    clueButtons.forEach((btn) => {
      btn.addEventListener('click', () => {
        const box = btn.closest('.clue-box');
        const qType = box.dataset.q;
        const val = btn.dataset.val;

        box.querySelectorAll('.choice-btn').forEach(b => {
          b.classList.remove('selected', 'correct-choice', 'wrong-choice');
        });

        userAnswers[qType] = val;
        btn.classList.add('selected');
        checkProgress();
      });
    });

    function checkProgress() {
      const target = solids[currentIdx];
      let answeredCount = 0;
      let allCorrect = true;

      ['surfaces', 'bases', 'shape'].forEach(q => {
        if (userAnswers[q]) {
          answeredCount++;
          const btn = document.querySelector(`.clue-box[data-q="${q}"] .choice-btn[data-val="${userAnswers[q]}"]`);
          if (userAnswers[q] === target[q]) {
            btn.classList.add('correct-choice');
          } else {
            btn.classList.add('wrong-choice');
            allCorrect = false;
          }
        } else {
          allCorrect = false;
        }
      });

      if (answeredCount === 3 && allCorrect) {
        badge.className = 'badge solved';
        badge.innerHTML = `✦ Solved: ${target.name}!`;
        banner.className = 'status-banner success';
        banner.textContent = `🎉 Brilliant detective work! It is a ${target.name}.`;
      } else if (answeredCount === 3) {
        badge.className = 'badge';
        badge.innerHTML = '🔍 Keep Checking';
        banner.className = 'status-banner';
        banner.textContent = 'Clue in red is incorrect — rotate 3D view and re-examine!';
      } else {
        badge.className = 'badge';
        badge.innerHTML = '🔍 Detective Mode';
        banner.className = 'status-banner';
        banner.textContent = `Selected ${answeredCount} of 3 clues...`;
      }
    }

    function updateUI() {
      clueButtons.forEach(b => b.classList.remove('selected', 'correct-choice', 'wrong-choice'));
      badge.className = 'badge';
      badge.innerHTML = '🔍 Detective Mode';
      banner.className = 'status-banner';
      banner.textContent = 'Identify all 3 clues to classify the solid!';
    }

    // Initial trigger
    loadSolid(0);
  </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">
  <style>
    * { box-sizing: border-box; margin: 0; padding: 0; }
    body {
      font-family: system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
      background: transparent;
      color: #1e2945;
      display: flex;
      flex-direction: column;
      align-items: center;
      justify-content: space-between;
      width: 100%;
      height: 100%;
      padding: 10px 8px;
      user-select: none;
      -webkit-user-select: none;
    }

    .diagram-area {
      position: relative;
      width: 100%;
      max-width: 340px;
      flex: 1;
      display: flex;
      align-items: center;
      justify-content: center;
    }

    svg {
      width: 100%;
      height: 100%;
      max-height: 290px;
      overflow: visible;
    }

    /* Cube Element Styles */
    .face {
      fill: rgba(34, 183, 255, 0.05);
      stroke: #cbd5e1;
      stroke-width: 1.5;
      transition: fill 0.3s ease, stroke 0.3s ease;
    }
    .face.active-single {
      fill: rgba(34, 183, 255, 0.4);
      stroke: #0284c7;
      stroke-width: 2;
    }
    .face.active-all {
      fill: rgba(34, 183, 255, 0.28);
      stroke: #0284c7;
      stroke-width: 1.5;
    }

    .edge {
      stroke: #94a3b8;
      stroke-width: 2;
      stroke-linecap: round;
      stroke-linejoin: round;
      transition: stroke 0.3s ease, stroke-width 0.3s ease;
    }
    .edge.dashed {
      stroke-dasharray: 4, 4;
      stroke: #cbd5e1;
    }
    .edge.active-single {
      stroke: #ff5733;
      stroke-width: 4;
    }
    .edge.active-all {
      stroke: #ff5733;
      stroke-width: 3.5;
      stroke-dasharray: none;
    }

    .vertex {
      fill: #64748b;
      transition: fill 0.3s ease, r 0.3s ease;
    }
    .vertex.active-single {
      fill: #f59e0b;
    }
    .vertex.active-all {
      fill: #f59e0b;
    }

    .pulse-ring {
      fill: none;
      stroke: #f59e0b;
      stroke-width: 2;
      opacity: 0;
      transform-origin: 235px 95px;
      animation: pulse 1.8s infinite ease-out;
    }

    @keyframes pulse {
      0% { r: 5px; opacity: 0.9; }
      100% { r: 16px; opacity: 0; }
    }

    /* Labels & Annotations */
    .label-group {
      transition: opacity 0.25s ease;
      pointer-events: none;
    }
    .label-box {
      font-size: 11px;
      font-weight: 700;
      fill: #ffffff;
      text-anchor: middle;
      dominant-baseline: central;
    }
    .leader-line {
      stroke-width: 1.5;
      fill: none;
    }

    /* Badge Counter */
    .counter-badge {
      position: absolute;
      top: 4px;
      right: 10px;
      background: #1e2945;
      color: #ffffff;
      font-size: 12px;
      font-weight: 700;
      padding: 4px 10px;
      border-radius: 20px;
      opacity: 0;
      transform: translateY(-4px);
      transition: opacity 0.25s ease, transform 0.25s ease;
    }
    .counter-badge.visible {
      opacity: 1;
      transform: translateY(0);
    }

    /* Button Controls */
    .controls {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 6px;
      width: 100%;
      max-width: 340px;
      margin-top: 4px;
    }
    .btn {
      background: #f1f5f9;
      border: 1px solid #e2e8f0;
      color: #475569;
      font-size: 11px;
      font-weight: 600;
      padding: 7px 2px;
      border-radius: 8px;
      cursor: pointer;
      text-align: center;
      transition: background 0.2s ease, color 0.2s ease, border-color 0.2s ease;
    }
    .btn.active {
      background: #1e2945;
      color: #ffffff;
      border-color: #1e2945;
    }
    .btn:active {
      opacity: 0.85;
    }
  </style>
</head>
<body>

  <div class="diagram-area">
    <div id="counterBadge" class="counter-badge">6 Faces</div>

    <svg viewBox="0 0 340 280">
      
      <polygon id="faceBack" class="face" points="105,55 225,55 225,175 105,175" />
      <polygon id="faceLeft" class="face" points="105,55 55,105 55,225 105,175" />
      <polygon id="faceBottom" class="face" points="55,225 175,225 225,175 105,175" />

      
      <line id="eBackLeft" class="edge dashed" x1="105" y1="55" x2="105" y2="175" />
      <line id="eBackBottom" class="edge dashed" x1="105" y1="175" x2="225" y2="175" />
      <line id="eBottomLeft" class="edge dashed" x1="55" y1="225" x2="105" y2="175" />

      
      <polygon id="faceTop" class="face" points="105,55 225,55 175,105 55,105" />
      <polygon id="faceRight" class="face" points="175,105 225,55 225,175 175,225" />
      <polygon id="faceFront" class="face active-single" points="55,105 175,105 175,225 55,225" />

      
      <line id="eTopBack" class="edge" x1="105" y1="55" x2="225" y2="55" />
      <line id="eTopLeft" class="edge" x1="105" y1="55" x2="55" y2="105" />
      <line id="eTopRight" class="edge" x1="225" y1="55" x2="175" y2="105" />
      <line id="eRightBack" class="edge" x1="225" y1="55" x2="225" y2="175" />
      <line id="eRightBottom" class="edge" x1="175" y1="225" x2="225" y2="175" />

      <line id="eFrontLeft" class="edge" x1="55" y1="105" x2="55" y2="225" />
      <line id="eFrontBottom" class="edge" x1="55" y1="225" x2="175" y2="225" />
      <line id="eFrontRight" class="edge" x1="175" y1="105" x2="175" y2="225" />
      <line id="eFrontTop" class="edge active-single" x1="55" y1="105" x2="175" y2="105" />

      
      <circle id="vPulse" class="pulse-ring" cx="175" cy="105" r="5" />

      
      <circle id="vBackTopLeft" class="vertex" cx="105" cy="55" r="4.5" />
      <circle id="vBackTopRight" class="vertex" cx="225" cy="55" r="4.5" />
      <circle id="vBackBottomRight" class="vertex" cx="225" cy="175" r="4.5" />
      <circle id="vBackBottomLeft" class="vertex" cx="105" cy="175" r="4.5" />

      <circle id="vFrontTopLeft" class="vertex" cx="55" cy="105" r="4.5" />
      <circle id="vFrontBottomLeft" class="vertex" cx="55" cy="225" r="4.5" />
      <circle id="vFrontBottomRight" class="vertex" cx="175" cy="225" r="4.5" />
      <circle id="vFrontTopRight" class="vertex active-single" cx="175" cy="105" r="5.5" />

      
      <g id="labelsOverview" class="label-group">
        
        <polyline class="leader-line" stroke="#ff5733" points="75,28 115,28 115,105" />
        <rect x="15" y="16" width="120" height="24" rx="12" fill="#ff5733" />
        <text class="label-box" x="75" y="28">Edge (line segment)</text>

        
        <polyline class="leader-line" stroke="#f59e0b" points="265,35 220,35 175,105" />
        <rect x="205" y="23" width="122" height="24" rx="12" fill="#f59e0b" />
        <text class="label-box" x="266" y="35">Vertex (corner point)</text>

        
        <polyline class="leader-line" stroke="#0284c7" points="70,256 115,256 115,165" />
        <rect x="15" y="244" width="116" height="24" rx="12" fill="#0284c7" />
        <text class="label-box" x="73" y="256">Face (flat surface)</text>
      </g>
    </svg>
  </div>

  
  <div class="controls">
    <button class="btn active" onclick="setMode('overview')">Anatomy</button>
    <button class="btn" onclick="setMode('faces')">6 Faces</button>
    <button class="btn" onclick="setMode('edges')">12 Edges</button>
    <button class="btn" onclick="setMode('vertices')">8 Vertices</button>
  </div>

  <script>
    const faces = document.querySelectorAll('.face');
    const edges = document.querySelectorAll('.edge');
    const vertices = document.querySelectorAll('.vertex');
    const singleFace = document.getElementById('faceFront');
    const singleEdge = document.getElementById('eFrontTop');
    const singleVertex = document.getElementById('vFrontTopRight');
    const pulseRing = document.getElementById('vPulse');
    const labelsOverview = document.getElementById('labelsOverview');
    const counterBadge = document.getElementById('counterBadge');
    const buttons = document.querySelectorAll('.btn');

    function resetAll() {
      faces.forEach(f => f.className.baseVal = 'face');
      edges.forEach(e => {
        const isDashed = e.id === 'eBackLeft' || e.id === 'eBackBottom' || e.id === 'eBottomLeft';
        e.className.baseVal = 'edge' + (isDashed ? ' dashed' : '');
      });
      vertices.forEach(v => {
        v.className.baseVal = 'vertex';
        v.setAttribute('r', '4.5');
      });
      pulseRing.style.display = 'none';
      labelsOverview.style.opacity = '0';
      counterBadge.classList.remove('visible');
    }

    function setMode(mode) {
      resetAll();
      buttons.forEach((b, i) => {
        const modes = ['overview', 'faces', 'edges', 'vertices'];
        b.classList.toggle('active', modes[i] === mode);
      });

      if (mode === 'overview') {
        singleFace.classList.add('active-single');
        singleEdge.classList.add('active-single');
        singleVertex.classList.add('active-single');
        singleVertex.setAttribute('r', '5.5');
        pulseRing.style.display = 'block';
        labelsOverview.style.opacity = '1';
      } else if (mode === 'faces') {
        faces.forEach(f => f.classList.add('active-all'));
        counterBadge.textContent = '6 Faces';
        counterBadge.style.background = '#0284c7';
        counterBadge.classList.add('visible');
      } else if (mode === 'edges') {
        edges.forEach(e => e.classList.add('active-all'));
        counterBadge.textContent = '12 Edges';
        counterBadge.style.background = '#ff5733';
        counterBadge.classList.add('visible');
      } else if (mode === 'vertices') {
        vertices.forEach(v => {
          v.classList.add('active-all');
          v.setAttribute('r', '5.5');
        });
        counterBadge.textContent = '8 Vertices';
        counterBadge.style.background = '#f59e0b';
        counterBadge.classList.add('visible');
      }
    }

    // Initialize in overview mode
    setMode('overview');
  </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, sans-serif;
      background: transparent;
      color: #1e2945;
      display: flex;
      flex-direction: column;
      gap: 8px;
      padding: 6px;
      user-select: none;
    }

    /* Filter Controls */
    .controls {
      display: flex;
      justify-content: center;
      gap: 6px;
      flex-wrap: wrap;
    }
    .btn-filter {
      background: #f1f5f9;
      border: 1px solid #cbd5e1;
      border-radius: 20px;
      padding: 4px 12px;
      font-size: 12px;
      font-weight: 600;
      color: #475569;
      cursor: pointer;
      transition: all 0.2s ease;
    }
    .btn-filter.active {
      background: #1e2945;
      color: #fff;
      border-color: #1e2945;
    }

    /* Column Headers */
    .columns-header {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 8px;
    }
    .col-badge {
      text-align: center;
      padding: 5px 8px;
      border-radius: 8px;
      font-size: 13px;
      font-weight: 700;
      letter-spacing: 0.2px;
    }
    .badge-poly {
      background: #dbeafe;
      color: #1d4ed8;
      border: 1px solid #bfdbfe;
    }
    .badge-curved {
      background: #fce7f3;
      color: #be185d;
      border: 1px solid #fbcfe8;
    }
    .col-sub {
      display: block;
      font-size: 11px;
      font-weight: 500;
      opacity: 0.85;
    }

    /* 2x2 Matrix */
    .matrix-grid {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 8px;
    }

    .shape-card {
      background: #ffffff;
      border: 1.5px solid #e2e8f0;
      border-radius: 10px;
      padding: 6px 8px;
      cursor: pointer;
      display: flex;
      flex-direction: column;
      align-items: center;
      position: relative;
      transition: box-shadow 0.2s ease, border-color 0.2s ease, opacity 0.25s ease;
    }
    .shape-card:hover {
      box-shadow: 0 4px 12px rgba(0,0,0,0.06);
    }
    .shape-card.dimmed {
      opacity: 0.25;
      pointer-events: none;
    }
    .shape-card.active-poly {
      border-color: #2563eb;
      box-shadow: 0 0 0 2px #93c5fd;
      background: #f8fafc;
    }
    .shape-card.active-curved {
      border-color: #db2777;
      box-shadow: 0 0 0 2px #f472b6;
      background: #fdf4f8;
    }

    .row-tag {
      position: absolute;
      top: 5px;
      left: 6px;
      font-size: 10px;
      font-weight: 700;
      color: #64748b;
      text-transform: uppercase;
      letter-spacing: 0.3px;
    }

    .card-title {
      font-size: 13px;
      font-weight: 700;
      margin-top: 14px;
      margin-bottom: 2px;
      color: #0f172a;
    }

    .svg-wrap {
      width: 100%;
      max-width: 110px;
      height: 72px;
      display: flex;
      align-items: center;
      justify-content: center;
    }
    svg {
      width: 100%;
      height: 100%;
      overflow: visible;
    }

    /* Key Insight Box */
    .insight-panel {
      background: #f8fafc;
      border: 1px solid #cbd5e1;
      border-radius: 8px;
      padding: 8px 12px;
      display: grid;
      grid-template-columns: auto 1fr;
      align-items: center;
      gap: 12px;
      min-height: 48px;
    }
    .insight-badge {
      font-size: 12px;
      font-weight: 700;
      padding: 4px 10px;
      border-radius: 6px;
      white-space: nowrap;
    }
    .insight-text {
      font-size: 12.5px;
      line-height: 1.35;
      color: #334155;
    }
    .insight-text strong {
      color: #0f172a;
    }
  </style>
</head>
<body>

  
  <div class="controls">
    <button class="btn-filter active" onclick="setFilter('all')">Show All</button>
    <button class="btn-filter" onclick="setFilter('2bases')">Two Bases</button>
    <button class="btn-filter" onclick="setFilter('apex')">Base + Apex</button>
  </div>

  
  <div class="columns-header">
    <div class="col-badge badge-poly">
      Polyhedra
      <span class="col-sub">Flat Faces Only</span>
    </div>
    <div class="col-badge badge-curved">
      Curved Solids
      <span class="col-sub">Smooth Curved Surfaces</span>
    </div>
  </div>

  
  <div class="matrix-grid">
    
    
    <div class="shape-card active-poly" id="card-prism" onclick="selectShape('prism')">
      <span class="row-tag">2 Bases</span>
      <div class="card-title">Prism</div>
      <div class="svg-wrap">
        <svg viewBox="0 0 110 75">
          
          <polygon points="20,24 60,8 92,20 52,36" fill="#bfdbfe" fill-opacity="0.8" stroke="#2563eb" stroke-width="1.5"/>
          
          <line x1="20" y1="58" x2="60" y2="42" stroke="#2563eb" stroke-width="1.2" stroke-dasharray="3,2"/>
          <line x1="60" y1="42" x2="92" y2="54" stroke="#2563eb" stroke-width="1.2" stroke-dasharray="3,2"/>
          <line x1="60" y1="8" x2="60" y2="42" stroke="#2563eb" stroke-width="1.2" stroke-dasharray="3,2"/>
          
          <polygon points="20,58 52,70 92,54 60,42" fill="#bfdbfe" fill-opacity="0.45" stroke="none"/>
          <line x1="20" y1="58" x2="52" y2="70" stroke="#2563eb" stroke-width="1.5"/>
          <line x1="52" y1="70" x2="92" y2="54" stroke="#2563eb" stroke-width="1.5"/>
          
          <line x1="20" y1="24" x2="20" y2="58" stroke="#2563eb" stroke-width="1.5"/>
          <line x1="52" y1="36" x2="52" y2="70" stroke="#2563eb" stroke-width="1.5"/>
          <line x1="92" y1="20" x2="92" y2="54" stroke="#2563eb" stroke-width="1.5"/>
        </svg>
      </div>
    </div>

    
    <div class="shape-card" id="card-cylinder" onclick="selectShape('cylinder')">
      <span class="row-tag">2 Bases</span>
      <div class="card-title">Cylinder</div>
      <div class="svg-wrap">
        <svg viewBox="0 0 110 75">
          
          <ellipse cx="55" cy="18" rx="34" ry="10" fill="#fbcfe8" fill-opacity="0.85" stroke="#db2777" stroke-width="1.5"/>
          
          <path d="M 21,54 A 34,10 0 0,1 89,54" fill="none" stroke="#db2777" stroke-width="1.2" stroke-dasharray="3,2"/>
          
          <path d="M 21,54 A 34,10 0 0,0 89,54" fill="#fbcfe8" fill-opacity="0.4" stroke="#db2777" stroke-width="1.5"/>
          
          <line x1="21" y1="18" x2="21" y2="54" stroke="#db2777" stroke-width="1.5"/>
          <line x1="89" y1="18" x2="89" y2="54" stroke="#db2777" stroke-width="1.5"/>
        </svg>
      </div>
    </div>

    
    <div class="shape-card" id="card-pyramid" onclick="selectShape('pyramid')">
      <span class="row-tag">1 Base + Apex</span>
      <div class="card-title">Pyramid</div>
      <div class="svg-wrap">
        <svg viewBox="0 0 110 75">
          
          <line x1="22" y1="52" x2="52" y2="40" stroke="#2563eb" stroke-width="1.2" stroke-dasharray="3,2"/>
          <line x1="52" y1="40" x2="88" y2="48" stroke="#2563eb" stroke-width="1.2" stroke-dasharray="3,2"/>
          <line x1="55" y1="10" x2="52" y2="40" stroke="#2563eb" stroke-width="1.2" stroke-dasharray="3,2"/>
          
          <polygon points="22,52 58,68 88,48 52,40" fill="#bfdbfe" fill-opacity="0.5" stroke="none"/>
          <line x1="22" y1="52" x2="58" y2="68" stroke="#2563eb" stroke-width="1.5"/>
          <line x1="58" y1="68" x2="88" y2="48" stroke="#2563eb" stroke-width="1.5"/>
          
          <line x1="55" y1="10" x2="22" y2="52" stroke="#2563eb" stroke-width="1.5"/>
          <line x1="55" y1="10" x2="58" y2="68" stroke="#2563eb" stroke-width="1.5"/>
          <line x1="55" y1="10" x2="88" y2="48" stroke="#2563eb" stroke-width="1.5"/>
          
          <circle cx="55" cy="10" r="3" fill="#1d4ed8"/>
          <text x="63" y="12" font-size="9" font-weight="700" fill="#1d4ed8">Apex</text>
        </svg>
      </div>
    </div>

    
    <div class="shape-card" id="card-cone" onclick="selectShape('cone')">
      <span class="row-tag">1 Base + Apex</span>
      <div class="card-title">Cone</div>
      <div class="svg-wrap">
        <svg viewBox="0 0 110 75">
          
          <path d="M 23,58 A 32,10 0 0,1 87,58" fill="none" stroke="#db2777" stroke-width="1.2" stroke-dasharray="3,2"/>
          
          <path d="M 23,58 A 32,10 0 0,0 87,58" fill="#fbcfe8" fill-opacity="0.45" stroke="#db2777" stroke-width="1.5"/>
          
          <line x1="55" y1="10" x2="23" y2="58" stroke="#db2777" stroke-width="1.5"/>
          <line x1="55" y1="10" x2="87" y2="58" stroke="#db2777" stroke-width="1.5"/>
          
          <circle cx="55" cy="10" r="3" fill="#be185d"/>
          <text x="63" y="12" font-size="9" font-weight="700" fill="#be185d">Apex</text>
        </svg>
      </div>
    </div>

  </div>

  
  <div class="insight-panel" id="insight-panel">
    <div class="insight-badge badge-poly" id="insight-badge">Prism</div>
    <div class="insight-text" id="insight-text">
      <strong>2 identical polygon bases</strong> connected by flat rectangular faces.
    </div>
  </div>

  <script>
    const data = {
      prism: {
        name: "Prism",
        type: "poly",
        badgeClass: "badge-poly",
        text: "<strong>2 polygon bases</strong> connected by flat rectangular faces. <em>Polyhedron (all flat faces).</em>"
      },
      cylinder: {
        name: "Cylinder",
        type: "curved",
        badgeClass: "badge-curved",
        text: "<strong>2 parallel circle bases</strong> connected by 1 curved surface. <em>Not a polyhedron.</em>"
      },
      pyramid: {
        name: "Pyramid",
        type: "poly",
        badgeClass: "badge-poly",
        text: "<strong>1 polygon base</strong> with triangular faces meeting at a sharp <strong>apex</strong>. <em>Polyhedron.</em>"
      },
      cone: {
        name: "Cone",
        type: "curved",
        badgeClass: "badge-curved",
        text: "<strong>1 circular base</strong> tapering smoothly to a single <strong>apex point</strong>. <em>Not a polyhedron.</em>"
      }
    };

    let currentFilter = 'all';

    function setFilter(filter) {
      currentFilter = filter;
      document.querySelectorAll('.btn-filter').forEach(btn => btn.classList.remove('active'));
      event.target.classList.add('active');

      const prism = document.getElementById('card-prism');
      const cylinder = document.getElementById('card-cylinder');
      const pyramid = document.getElementById('card-pyramid');
      const cone = document.getElementById('card-cone');

      if (filter === 'all') {
        [prism, cylinder, pyramid, cone].forEach(c => c.classList.remove('dimmed'));
      } else if (filter === '2bases') {
        prism.classList.remove('dimmed');
        cylinder.classList.remove('dimmed');
        pyramid.classList.add('dimmed');
        cone.classList.add('dimmed');
        selectShape('prism');
      } else if (filter === 'apex') {
        prism.classList.add('dimmed');
        cylinder.classList.add('dimmed');
        pyramid.classList.remove('dimmed');
        cone.classList.remove('dimmed');
        selectShape('pyramid');
      }
    }

    function selectShape(id) {
      document.querySelectorAll('.shape-card').forEach(card => {
        card.classList.remove('active-poly', 'active-curved');
      });

      const card = document.getElementById('card-' + id);
      const info = data[id];

      if (info.type === 'poly') {
        card.classList.add('active-poly');
      } else {
        card.classList.add('active-curved');
      }

      const badge = document.getElementById('insight-badge');
      badge.className = 'insight-badge ' + info.badgeClass;
      badge.textContent = info.name;

      document.getElementById('insight-text').innerHTML = info.text;
    }
  </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>Euler's Formula Explorer</title>
  <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;
      width: 100%;
      min-height: 100%;
      display: flex;
      flex-direction: column;
      align-items: center;
      padding: 10px;
      gap: 10px;
    }

    /* Shape Selector */
    .tabs {
      display: flex;
      flex-wrap: wrap;
      gap: 6px;
      justify-content: center;
      width: 100%;
      max-width: 360px;
    }
    .tab-btn {
      background: #f1f5f9;
      border: 1px solid #cbd5e1;
      border-radius: 8px;
      padding: 6px 10px;
      font-size: 13px;
      font-weight: 600;
      color: #475569;
      cursor: pointer;
      transition: all 0.2s ease;
    }
    .tab-btn.active {
      background: #2563eb;
      color: #ffffff;
      border-color: #2563eb;
      box-shadow: 0 2px 6px rgba(37, 99, 235, 0.25);
    }

    /* Main Display Area */
    .viewer {
      width: 100%;
      max-width: 340px;
      height: 130px;
      background: #f8fafc;
      border-radius: 12px;
      border: 1px solid #e2e8f0;
      display: flex;
      align-items: center;
      justify-content: center;
      position: relative;
    }
    .shape-svg {
      width: 100%;
      height: 100%;
      max-height: 120px;
    }

    /* Stats Grid */
    .stats-row {
      display: flex;
      gap: 8px;
      width: 100%;
      max-width: 340px;
      justify-content: space-between;
    }
    .stat-box {
      flex: 1;
      background: #ffffff;
      border: 1px solid #e2e8f0;
      border-radius: 8px;
      padding: 6px 4px;
      text-align: center;
    }
    .stat-label {
      font-size: 11px;
      font-weight: 700;
      text-transform: uppercase;
      letter-spacing: 0.5px;
    }
    .stat-box.faces .stat-label { color: #2563eb; }
    .stat-box.verts .stat-label { color: #d97706; }
    .stat-box.edges .stat-label { color: #7c3aed; }
    .stat-value {
      font-size: 18px;
      font-weight: 800;
      color: #1e2945;
      margin-top: 2px;
    }

    /* Equation Card */
    .calc-card {
      width: 100%;
      max-width: 340px;
      background: #f8fafc;
      border: 1px solid #e2e8f0;
      border-radius: 10px;
      padding: 10px 12px;
      display: flex;
      flex-direction: column;
      align-items: center;
      gap: 8px;
    }
    .equation-line {
      font-size: 16px;
      font-weight: 800;
      display: flex;
      align-items: center;
      gap: 6px;
      letter-spacing: 0.5px;
    }
    .badge-f { color: #2563eb; }
    .badge-v { color: #d97706; }
    .badge-e { color: #7c3aed; }
    .badge-res { color: #16a34a; }

    .status-badge {
      font-size: 12px;
      font-weight: 700;
      padding: 4px 10px;
      border-radius: 999px;
      text-align: center;
      width: 100%;
      display: flex;
      align-items: center;
      justify-content: center;
      gap: 4px;
    }
    .status-badge.valid {
      background: #dcfce7;
      color: #15803d;
      border: 1px solid #86efac;
    }
    .status-badge.invalid {
      background: #fef3c7;
      color: #92400e;
      border: 1px solid #fcd34d;
    }
  </style>
</head>
<body>

  
  <div class="tabs" id="tabGroup">
    <button class="tab-btn active" data-shape="prism">Triangular Prism</button>
    <button class="tab-btn" data-shape="cube">Cube</button>
    <button class="tab-btn" data-shape="pyramid">Square Pyramid</button>
    <button class="tab-btn" data-shape="cylinder">Cylinder</button>
    <button class="tab-btn" data-shape="cone">Cone</button>
  </div>

  
  <div class="viewer">
    <svg id="shapeSvg" class="shape-svg" viewBox="0 0 200 120"></svg>
  </div>

  
  <div class="stats-row">
    <div class="stat-box faces">
      <div class="stat-label">Faces (F)</div>
      <div class="stat-value" id="valF">5</div>
    </div>
    <div class="stat-box verts">
      <div class="stat-label">Vertices (V)</div>
      <div class="stat-value" id="valV">6</div>
    </div>
    <div class="stat-box edges">
      <div class="stat-label">Edges (E)</div>
      <div class="stat-value" id="valE">9</div>
    </div>
  </div>

  
  <div class="calc-card">
    <div class="equation-line" id="equationBox">
      <span class="badge-f">5</span> + <span class="badge-v">6</span> − <span class="badge-e">9</span> = <span class="badge-res">2</span>
    </div>
    <div id="statusBadge" class="status-badge valid">
      <span>✓</span> F + V − E = 2 (Euler's Formula holds!)
    </div>
  </div>

  <script>
    const shapes = {
      prism: {
        f: 5, v: 6, e: 9,
        valid: true,
        render: `
          
          <line x1="50" y1="85" x2="130" y2="85" stroke="#cbd5e1" stroke-width="1.5" stroke-dasharray="3,3" />
          <line x1="50" y1="85" x2="80" y2="35" stroke="#cbd5e1" stroke-width="1.5" stroke-dasharray="3,3" />
          <line x1="50" y1="85" x2="70" y2="105" stroke="#cbd5e1" stroke-width="1.5" stroke-dasharray="3,3" />
          
          <polygon points="80,35 160,35 150,105 70,105" fill="#3b82f6" fill-opacity="0.12" />
          <polygon points="80,35 100,15 180,15 160,35" fill="#3b82f6" fill-opacity="0.22" />
          <polygon points="160,35 180,15 150,105" fill="#3b82f6" fill-opacity="0.18" />
          
          <line x1="80" y1="35" x2="100" y2="15" stroke="#4f46e5" stroke-width="2" />
          <line x1="100" y1="15" x2="180" y2="15" stroke="#4f46e5" stroke-width="2" />
          <line x1="180" y1="15" x2="160" y2="35" stroke="#4f46e5" stroke-width="2" />
          <line x1="80" y1="35" x2="160" y2="35" stroke="#4f46e5" stroke-width="2" />
          <line x1="80" y1="35" x2="70" y2="105" stroke="#4f46e5" stroke-width="2" />
          <line x1="160" y1="35" x2="150" y2="105" stroke="#4f46e5" stroke-width="2" />
          <line x1="180" y1="15" x2="150" y2="105" stroke="#4f46e5" stroke-width="2" />
          <line x1="70" y1="105" x2="150" y2="105" stroke="#4f46e5" stroke-width="2" />
          
          <circle cx="80" cy="35" r="4" fill="#d97706" />
          <circle cx="100" cy="15" r="4" fill="#d97706" />
          <circle cx="180" cy="15" r="4" fill="#d97706" />
          <circle cx="160" cy="35" r="4" fill="#d97706" />
          <circle cx="70" cy="105" r="4" fill="#d97706" />
          <circle cx="150" cy="105" r="4" fill="#d97706" />
          <circle cx="50" cy="85" r="3" fill="#cbd5e1" />
        `
      },
      cube: {
        f: 6, v: 8, e: 12,
        valid: true,
        render: `
          
          <line x1="70" y1="50" x2="70" y2="105" stroke="#cbd5e1" stroke-width="1.5" stroke-dasharray="3,3" />
          <line x1="70" y1="50" x2="100" y2="20" stroke="#cbd5e1" stroke-width="1.5" stroke-dasharray="3,3" />
          <line x1="70" y1="105" x2="100" y2="75" stroke="#cbd5e1" stroke-width="1.5" stroke-dasharray="3,3" />
          
          <polygon points="60,40 120,40 120,95 60,95" fill="#3b82f6" fill-opacity="0.15" />
          <polygon points="60,40 100,20 160,20 120,40" fill="#3b82f6" fill-opacity="0.25" />
          <polygon points="120,40 160,20 160,75 120,95" fill="#3b82f6" fill-opacity="0.2" />
          
          <rect x="60" y="40" width="60" height="55" fill="none" stroke="#4f46e5" stroke-width="2" />
          <line x1="60" y1="40" x2="100" y2="20" stroke="#4f46e5" stroke-width="2" />
          <line x1="120" y1="40" x2="160" y2="20" stroke="#4f46e5" stroke-width="2" />
          <line x1="120" y1="95" x2="160" y2="75" stroke="#4f46e5" stroke-width="2" />
          <line x1="100" y1="20" x2="160" y2="20" stroke="#4f46e5" stroke-width="2" />
          <line x1="160" y1="20" x2="160" y2="75" stroke="#4f46e5" stroke-width="2" />
          
          <circle cx="60" cy="40" r="4" fill="#d97706" />
          <circle cx="120" cy="40" r="4" fill="#d97706" />
          <circle cx="120" cy="95" r="4" fill="#d97706" />
          <circle cx="60" cy="95" r="4" fill="#d97706" />
          <circle cx="100" cy="20" r="4" fill="#d97706" />
          <circle cx="160" cy="20" r="4" fill="#d97706" />
          <circle cx="160" cy="75" r="4" fill="#d97706" />
          <circle cx="70" cy="50" r="3" fill="#cbd5e1" />
        `
      },
      pyramid: {
        f: 5, v: 5, e: 8,
        valid: true,
        render: `
          
          <line x1="65" y1="75" x2="135" y2="75" stroke="#cbd5e1" stroke-width="1.5" stroke-dasharray="3,3" />
          <line x1="65" y1="75" x2="90" y2="105" stroke="#cbd5e1" stroke-width="1.5" stroke-dasharray="3,3" />
          <line x1="65" y1="75" x2="100" y2="18" stroke="#cbd5e1" stroke-width="1.5" stroke-dasharray="3,3" />
          
          <polygon points="100,18 90,105 160,105" fill="#3b82f6" fill-opacity="0.18" />
          <polygon points="100,18 160,105 135,75" fill="#3b82f6" fill-opacity="0.25" />
          
          <line x1="100" y1="18" x2="90" y2="105" stroke="#4f46e5" stroke-width="2" />
          <line x1="100" y1="18" x2="160" y2="105" stroke="#4f46e5" stroke-width="2" />
          <line x1="100" y1="18" x2="135" y2="75" stroke="#4f46e5" stroke-width="2" />
          <line x1="90" y1="105" x2="160" y2="105" stroke="#4f46e5" stroke-width="2" />
          <line x1="160" y1="105" x2="135" y2="75" stroke="#4f46e5" stroke-width="2" />
          
          <circle cx="100" cy="18" r="4" fill="#d97706" />
          <circle cx="90" cy="105" r="4" fill="#d97706" />
          <circle cx="160" cy="105" r="4" fill="#d97706" />
          <circle cx="135" cy="75" r="4" fill="#d97706" />
          <circle cx="65" cy="75" r="3" fill="#cbd5e1" />
        `
      },
      cylinder: {
        f: '—', v: '—', e: '—',
        valid: false,
        render: `
          
          <path d="M60,95 A40,12 0 0,1 140,95" fill="none" stroke="#cbd5e1" stroke-width="1.5" stroke-dasharray="3,3" />
          
          <path d="M60,25 L60,95 A40,12 0 0,0 140,95 L140,25 Z" fill="#3b82f6" fill-opacity="0.15" />
          
          <path d="M60,95 A40,12 0 0,0 140,95" fill="none" stroke="#4f46e5" stroke-width="2" />
          
          <line x1="60" y1="25" x2="60" y2="95" stroke="#4f46e5" stroke-width="2" />
          <line x1="140" y1="25" x2="140" y2="95" stroke="#4f46e5" stroke-width="2" />
          
          <ellipse cx="100" cy="25" rx="40" ry="12" fill="#3b82f6" fill-opacity="0.25" stroke="#4f46e5" stroke-width="2" />
        `
      },
      cone: {
        f: '—', v: '—', e: '—',
        valid: false,
        render: `
          
          <path d="M60,95 A40,12 0 0,1 140,95" fill="none" stroke="#cbd5e1" stroke-width="1.5" stroke-dasharray="3,3" />
          
          <path d="M100,18 L60,95 A40,12 0 0,0 140,95 Z" fill="#3b82f6" fill-opacity="0.18" />
          
          <path d="M60,95 A40,12 0 0,0 140,95" fill="none" stroke="#4f46e5" stroke-width="2" />
          
          <line x1="100" y1="18" x2="60" y2="95" stroke="#4f46e5" stroke-width="2" />
          <line x1="100" y1="18" x2="140" y2="95" stroke="#4f46e5" stroke-width="2" />
          
          <circle cx="100" cy="18" r="3.5" fill="#4f46e5" />
        `
      }
    };

    function updateShape(key) {
      const data = shapes[key];
      if (!data) return;

      // Update active button
      document.querySelectorAll('.tab-btn').forEach(btn => {
        btn.classList.toggle('active', btn.dataset.shape === key);
      });

      // Update SVG
      document.getElementById('shapeSvg').innerHTML = data.render;

      // Update Counters
      document.getElementById('valF').textContent = data.f;
      document.getElementById('valV').textContent = data.v;
      document.getElementById('valE').textContent = data.e;

      // Update Equation & Badge
      const eqBox = document.getElementById('equationBox');
      const badge = document.getElementById('statusBadge');

      if (data.valid) {
        eqBox.innerHTML = `<span class="badge-f">${data.f}</span> + <span class="badge-v">${data.v}</span> − <span class="badge-e">${data.e}</span> = <span class="badge-res">2</span>`;
        badge.className = 'status-badge valid';
        badge.innerHTML = `<span>✓</span> F + V − E = 2 (Euler's Formula holds!)`;
      } else {
        eqBox.innerHTML = `<span>Curved Surface (Not a Polyhedron)</span>`;
        badge.className = 'status-badge invalid';
        badge.innerHTML = `<span>⚠</span> Formula does not apply (Curved boundaries)`;
      }
    }

    // Attach Click Events
    document.querySelectorAll('.tab-btn').forEach(btn => {
      btn.addEventListener('click', () => updateShape(btn.dataset.shape));
    });

    // Initial render
    updateShape('prism');
  </script>
</body>
</html>

OGM.8.GEO.10

Aligned learning resources

Related diagrams