<!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>Three Types of Models</title>
  <style>
    * {
      box-sizing: border-box;
      margin: 0;
      padding: 0;
    }

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

    .grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 12px;
      width: 100%;
      max-width: 640px;
    }

    @media (max-width: 480px) {
      .grid {
        grid-template-columns: 1fr;
        gap: 10px;
      }
    }

    .model-card {
      background: #fafbfc;
      border: 1.5px solid #e6e6e6;
      border-radius: 14px;
      padding: 12px 8px;
      display: flex;
      flex-direction: column;
      align-items: center;
      text-align: center;
      transition: box-shadow 0.25s ease, background-color 0.25s ease;
      cursor: pointer;
      user-select: none;
    }

    .model-card:hover {
      box-shadow: 0 4px 12px rgba(34, 183, 255, 0.15);
      background: #ffffff;
    }

    .model-card.active {
      box-shadow: 0 0 0 2px #22b7ff;
      background: #f0f9ff;
    }

    .card-title {
      font-size: 15px;
      font-weight: 700;
      color: #1e2945;
      margin-bottom: 8px;
    }

    .visual-area {
      width: 100%;
      height: 120px;
      display: flex;
      align-items: center;
      justify-content: center;
      position: relative;
    }

    /* Card 1: Smaller */
    .compare-box {
      display: flex;
      align-items: center;
      justify-content: center;
      gap: 10px;
      width: 100%;
    }

    .real-plane {
      font-size: 40px;
      opacity: 0.35;
      filter: grayscale(40%);
      line-height: 1;
    }

    .arrow-icon {
      font-size: 18px;
      color: #22b7ff;
      font-weight: 900;
    }

    .toy-plane {
      font-size: 24px;
      line-height: 1;
      background: #e0f2fe;
      padding: 8px;
      border-radius: 12px;
      border: 1px dashed #0284c7;
    }

    /* Card 2: Bigger */
    .tiny-bug {
      font-size: 14px;
      opacity: 0.45;
      line-height: 1;
    }

    .big-bug-wrap {
      position: relative;
      background: #fee2e2;
      border: 1px dashed #ef4444;
      border-radius: 12px;
      padding: 6px 10px;
      display: flex;
      flex-direction: column;
      align-items: center;
    }

    .big-bug {
      font-size: 38px;
      line-height: 1;
    }

    .zoom-badge {
      font-size: 11px;
      font-weight: 700;
      color: #dc2626;
      background: #ffffff;
      padding: 1px 6px;
      border-radius: 6px;
      margin-top: 2px;
    }

    /* Card 3: Simpler */
    .flower-svg {
      width: 130px;
      height: 110px;
    }

    .tag-label {
      font-size: 10px;
      font-weight: 600;
      fill: #4b5563;
    }
  </style>
</head>
<body>

  <div class="grid">
    
    <div class="model-card active" onclick="selectCard(this)">
      <div class="card-title">Made Smaller</div>
      <div class="visual-area">
        <div class="compare-box">
          <div class="real-plane" title="Giant Jet">✈️</div>
          <div class="arrow-icon">→</div>
          <div class="toy-plane" title="Toy Model">✈️</div>
        </div>
      </div>
    </div>

    
    <div class="model-card" onclick="selectCard(this)">
      <div class="card-title">Made Bigger</div>
      <div class="visual-area">
        <div class="compare-box">
          <div class="tiny-bug" title="Real tiny ladybug">🐞</div>
          <div class="arrow-icon">→</div>
          <div class="big-bug-wrap" title="Giant Model Ladybug">
            <div class="big-bug">🐞</div>
            <div class="zoom-badge">🔍 Zoom</div>
          </div>
        </div>
      </div>
    </div>

    
    <div class="model-card" onclick="selectCard(this)">
      <div class="card-title">Simpler Drawing</div>
      <div class="visual-area">
        <svg class="flower-svg" viewBox="0 0 140 120">
          
          <circle cx="70" cy="30" r="14" fill="#f43f5e" />
          <circle cx="70" cy="30" r="6" fill="#facc15" />
          
          
          <line x1="86" y1="28" x2="108" y2="22" stroke="#94a3b8" stroke-width="1.5" />
          <text x="110" y="24" class="tag-label">petal</text>

          
          <line x1="70" y1="44" x2="70" y2="85" stroke="#16a34a" stroke-width="3" stroke-linecap="round" />
          <ellipse cx="60" cy="62" rx="7" ry="3" fill="#22c55e" transform="rotate(-25 60 62)" />
          
          
          <line x1="73" y1="62" x2="100" y2="62" stroke="#94a3b8" stroke-width="1.5" />
          <text x="103" y="65" class="tag-label">stem</text>

          
          <line x1="40" y1="85" x2="100" y2="85" stroke="#d97706" stroke-width="1.5" stroke-dasharray="3,2" />

          
          <path d="M 70 85 Q 65 98 58 108 M 70 85 Q 72 98 70 112 M 70 85 Q 76 98 84 107" fill="none" stroke="#b45309" stroke-width="1.8" stroke-linecap="round" />
          
          
          <line x1="80" y1="102" x2="100" y2="102" stroke="#94a3b8" stroke-width="1.5" />
          <text x="103" y="105" class="tag-label">roots</text>
        </svg>
      </div>
    </div>
  </div>

  <script>
    function selectCard(element) {
      document.querySelectorAll('.model-card').forEach(card => {
        card.classList.remove('active');
      });
      element.classList.add('active');
    }
  </script>
</body>
</html>

What Is a Scientific Model?

<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>Real Volcano vs. Student Model</title>
  <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;
      display: flex;
      flex-direction: column;
      align-items: center;
      justify-content: center;
      padding: 12px;
      min-height: 100vh;
    }
    .container {
      width: 100%;
      max-width: 680px;
      display: flex;
      flex-direction: column;
      gap: 12px;
    }
    .header {
      text-align: center;
    }
    .header h1 {
      font-size: 1.25rem;
      font-weight: 800;
      color: #0f172a;
      letter-spacing: -0.02em;
      margin-bottom: 3px;
    }
    .header p {
      font-size: 0.85rem;
      color: #64748b;
    }
    .comparison-grid {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 16px;
      width: 100%;
    }
    @media (max-width: 540px) {
      .comparison-grid {
        grid-template-columns: 1fr;
        gap: 16px;
      }
    }
    .section-col {
      display: flex;
      flex-direction: column;
      align-items: center;
      text-align: center;
    }
    .badge {
      font-size: 11.5px;
      font-weight: 700;
      padding: 4px 12px;
      border-radius: 999px;
      display: inline-flex;
      align-items: center;
      gap: 6px;
      margin-bottom: 4px;
      text-transform: uppercase;
      letter-spacing: 0.03em;
    }
    .badge-real {
      background: #ffedd5;
      color: #c2410c;
    }
    .badge-model {
      background: #e0f2fe;
      color: #0369a1;
    }
    .section-desc {
      font-size: 0.85rem;
      font-weight: 600;
      color: #475569;
      min-height: 18px;
      margin-bottom: 6px;
    }
    .svg-wrapper {
      width: 100%;
      max-width: 300px;
      height: 175px;
      display: flex;
      align-items: center;
      justify-content: center;
    }
    svg {
      width: 100%;
      height: 100%;
      overflow: visible;
    }
    .materials-legend {
      display: flex;
      flex-wrap: wrap;
      justify-content: center;
      gap: 6px;
      margin-top: 6px;
    }
    .mat-tag {
      font-size: 11px;
      font-weight: 600;
      color: #64748b;
      background: #f1f5f9;
      padding: 2px 8px;
      border-radius: 6px;
      display: inline-flex;
      align-items: center;
      gap: 4px;
    }
    .mat-dot {
      width: 8px;
      height: 8px;
      border-radius: 50%;
    }
    .btn-action {
      margin-top: 8px;
      background: #0284c7;
      color: #ffffff;
      border: none;
      font-size: 12.5px;
      font-weight: 700;
      padding: 7px 16px;
      border-radius: 999px;
      cursor: pointer;
      display: inline-flex;
      align-items: center;
      gap: 6px;
      transition: background-color 0.5s ease, opacity 0.5s ease;
    }
    .btn-action:hover {
      background: #0369a1;
    }
    .btn-action:active {
      opacity: 0.85;
    }

    /* Safe, continuous, non-strobing animations (duration >= 500ms) */
    .smoke-puff-slow {
      animation: driftSmoke 6s infinite ease-out;
      transform-origin: 100px 75px;
    }
    .smoke-puff-slow-2 {
      animation: driftSmoke 6s infinite ease-out 3s;
      transform-origin: 100px 75px;
    }
    @keyframes driftSmoke {
      0% {
        transform: translateY(0) scale(0.7);
        opacity: 0.75;
      }
      50% {
        opacity: 0.4;
      }
      100% {
        transform: translateY(-28px) scale(1.3);
        opacity: 0;
      }
    }

    /* Model Foam Animation */
    .model-foam-layer {
      opacity: 0;
      transform: scale(0.3);
      transform-origin: 100px 78px;
      transition: transform 0.7s cubic-bezier(0.16, 1, 0.3, 1), opacity 0.6s ease;
    }
    .is-erupting .model-foam-layer {
      opacity: 1;
      transform: scale(1);
    }
    .foam-bubble {
      animation: gentleFloat 3.5s infinite ease-in-out;
    }
    .foam-bubble-2 {
      animation: gentleFloat 3.5s infinite ease-in-out 1.75s;
    }
    @keyframes gentleFloat {
      0%, 100% { transform: translateY(0); }
      50% { transform: translateY(-2.5px); }
    }
  </style>
</head>
<body>
  <div class="container">
    <div class="header">
      <h1>Volcano Science Investigation</h1>
      <p>Comparing real geological hazards with hands-on classroom modeling</p>
    </div>

    <div class="comparison-grid">
      
      <div class="section-col">
        <div class="badge badge-real">🌋 Step 1 • Real World</div>
        <div class="section-desc">Too hot and dangerous!</div>
        <div class="svg-wrapper">
          <svg viewBox="0 0 200 170" aria-label="Real Volcano Illustration">
            <defs>
              <linearGradient id="skyGrad" x1="0" y1="0" x2="0" y2="1">
                <stop offset="0%" stop-color="#fed7aa" stop-opacity="0.55" />
                <stop offset="100%" stop-color="#fff" stop-opacity="0" />
              </linearGradient>
              <linearGradient id="lavaStream" x1="0" y1="0" x2="0" y2="1">
                <stop offset="0%" stop-color="#ef4444" />
                <stop offset="100%" stop-color="#f97316" />
              </linearGradient>
            </defs>
            
            <ellipse cx="100" cy="115" rx="80" ry="45" fill="url(#skyGrad)" />

            
            <circle class="smoke-puff-slow" cx="95" cy="55" r="14" fill="#78716c" opacity="0.75" />
            <circle class="smoke-puff-slow-2" cx="108" cy="48" r="12" fill="#a8a29e" opacity="0.6" />

            
            <path d="M96 75 C94 45, 102 38, 102 38 C102 38, 110 45, 106 75 Z" fill="url(#lavaStream)" />
            <circle cx="92" cy="48" r="3.5" fill="#facc15" />
            <circle cx="109" cy="44" r="2.5" fill="#f97316" />

            
            <polygon points="25,150 82,75 118,75 175,150" fill="#44403c" />
            
            <polygon points="25,150 82,75 100,150" fill="#57534e" />
            <polygon points="100,150 118,75 175,150" fill="#292524" />

            
            <path d="M92 76 Q86 105 78 132" stroke="#ea580c" stroke-width="4" stroke-linecap="round" fill="none" />
            <path d="M92 76 Q87 105 80 128" stroke="#fde047" stroke-width="1.8" stroke-linecap="round" fill="none" />
            <path d="M106 76 Q112 102 122 138" stroke="#dc2626" stroke-width="4" stroke-linecap="round" fill="none" />
            <path d="M106 76 Q111 102 120 134" stroke="#f97316" stroke-width="1.8" stroke-linecap="round" fill="none" />

            
            <rect x="15" y="150" width="170" height="6" rx="3" fill="#cbd5e1" />

            
            <g transform="translate(156, 14)">
              <circle cx="11" cy="11" r="11" fill="#ef4444" />
              <text x="11" y="15" fill="#ffffff" font-size="12" font-weight="900" text-anchor="middle">✕</text>
            </g>
          </svg>
        </div>
        <div class="materials-legend">
          <span class="mat-tag"><span class="mat-dot" style="background:#dc2626;"></span>1000°C Magma</span>
          <span class="mat-tag"><span class="mat-dot" style="background:#78716c;"></span>Ash &amp; Gas</span>
        </div>
      </div>

      
      <div class="section-col" id="modelContainer">
        <div class="badge badge-model">🧪 Step 2 • Student Model</div>
        <div class="section-desc">Safe to test at school!</div>
        <div class="svg-wrapper">
          <svg viewBox="0 0 200 170" aria-label="Student Model Volcano Illustration">
            
            <rect x="15" y="150" width="170" height="6" rx="3" fill="#cbd5e1" />

            
            <path d="M85 82 L89 150 L111 150 L115 82 Z" fill="#bae6fd" stroke="#0284c7" stroke-width="1.5" stroke-dasharray="3,2" opacity="0.9" />
            <ellipse cx="100" cy="82" rx="15" ry="3.5" fill="#e0f2fe" stroke="#0284c7" stroke-width="1.2" />

            
            <path d="M48 150 L84 82 Q100 79 116 82 L152 150 Z" fill="#9a3412" />
            <path d="M60 150 L88 82 Q100 80 112 82 L140 150 Z" fill="#b45309" opacity="0.35" />

            
            <path d="M91 83 Q87 108 82 125" stroke="#dc2626" stroke-width="3.5" stroke-linecap="round" fill="none" />
            <path d="M107 83 Q114 104 116 122" stroke="#ea580c" stroke-width="3" stroke-linecap="round" fill="none" />
            <path d="M100 83 Q102 100 100 115" stroke="#ef4444" stroke-width="2.5" stroke-linecap="round" fill="none" />

            
            
            <g transform="translate(14, 118)">
              
              <rect x="7" y="0" width="8" height="6" rx="1.5" fill="#e2e8f0" stroke="#94a3b8" stroke-width="0.5" />
              
              <rect x="0" y="5" width="22" height="27" rx="3.5" fill="#ef4444" />
              
              <rect x="2" y="11" width="18" height="15" rx="2" fill="#ffffff" />
              <text x="11" y="21" font-size="5.5" fill="#ef4444" font-weight="800" text-anchor="middle" letter-spacing="0.2">PAINT</text>
            </g>

            
            <g transform="translate(38, 142) rotate(-22)">
              <rect x="0" y="0" width="20" height="3" rx="1" fill="#b45309" />
              <rect x="20" y="0" width="5" height="3" fill="#94a3b8" />
              <polygon points="25,0 30,1.5 25,3" fill="#dc2626" />
            </g>

            
            <g transform="translate(162, 122)">
              <rect x="0" y="8" width="24" height="20" rx="3.5" fill="#78350f" />
              <rect x="2" y="10" width="20" height="9" rx="2" fill="#9a3412" />
              
              <rect x="3" y="20" width="18" height="7" rx="1.5" fill="#fef3c7" />
              <text x="12" y="25.5" font-size="5.5" fill="#78350f" font-weight="800" text-anchor="middle" letter-spacing="0.2">CLAY</text>
            </g>

            
            <g class="model-foam-layer">
              <ellipse cx="100" cy="80" rx="22" ry="9" fill="#f87171" />
              <circle class="foam-bubble" cx="92" cy="70" r="8" fill="#fca5a5" />
              <circle class="foam-bubble-2" cx="104" cy="66" r="10" fill="#ef4444" />
              <circle class="foam-bubble" cx="114" cy="72" r="7" fill="#fca5a5" />
              
              <circle cx="85" cy="62" r="3.5" fill="#fef2f2" />
              <circle cx="101" cy="54" r="4.5" fill="#ffffff" />
              <circle cx="118" cy="60" r="3.5" fill="#fef2f2" />
              
              <path d="M88 84 Q82 96 85 106" stroke="#f87171" stroke-width="3" stroke-linecap="round" fill="none" />
              <path d="M110 84 Q116 94 113 104" stroke="#f87171" stroke-width="3" stroke-linecap="round" fill="none" />
            </g>

            
            <g transform="translate(156, 14)">
              <circle cx="11" cy="11" r="11" fill="#16a34a" />
              <text x="11" y="15" fill="#ffffff" font-size="12" font-weight="900" text-anchor="middle">✓</text>
            </g>
          </svg>
        </div>
        <div class="materials-legend">
          <span class="mat-tag"><span class="mat-dot" style="background:#0284c7;"></span>Plastic Cup</span>
          <span class="mat-tag"><span class="mat-dot" style="background:#9a3412;"></span>Brown Clay</span>
          <span class="mat-tag"><span class="mat-dot" style="background:#ef4444;"></span>Red Paint</span>
        </div>
        <button class="btn-action" id="btnToggleEruption" type="button">
          <span id="btnIcon">⏸</span> <span id="btnText">Reset Model</span>
        </button>
      </div>
    </div>
  </div>

  <script>
    const modelContainer = document.getElementById('modelContainer');
    const btnToggle = document.getElementById('btnToggleEruption');
    const btnIcon = document.getElementById('btnIcon');
    const btnText = document.getElementById('btnText');

    let isErupting = true;
    modelContainer.classList.add('is-erupting');

    btnToggle.addEventListener('click', () => {
      isErupting = !isErupting;
      if (isErupting) {
        modelContainer.classList.add('is-erupting');
        btnIcon.textContent = '⏸';
        btnText.textContent = 'Reset Model';
      } else {
        modelContainer.classList.remove('is-erupting');
        btnIcon.textContent = '▶';
        btnText.textContent = 'Erupt Model';
      }
    });
  </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;
      font-family: system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
    }

    :root {
      --primary: #22b7ff;
      --primary-dark: #0093dc;
      --primary-light: #e0f4ff;
      --text: #1e2945;
      --muted: #64748b;
      --card-bg: #f8fafc;
      --border: #e2e8f0;
      --space-bg: #0b1329;
    }

    body {
      background: transparent;
      color: var(--text);
      display: flex;
      flex-direction: column;
      align-items: center;
      justify-content: center;
      min-height: 100%;
      padding: 12px;
      user-select: none;
      -webkit-user-select: none;
    }

    .container {
      width: 100%;
      max-width: 600px;
      display: flex;
      flex-direction: column;
      gap: 12px;
    }

    /* Comparison Area */
    .compare-wrap {
      position: relative;
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 16px;
      align-items: stretch;
    }

    .panel {
      background: var(--card-bg);
      border: 2px solid var(--border);
      border-radius: 18px;
      padding: 14px 10px 12px;
      display: flex;
      flex-direction: column;
      align-items: center;
      text-align: center;
      transition: border-color 0.3s ease, box-shadow 0.3s ease;
      position: relative;
      overflow: hidden;
    }

    .panel.active {
      border-color: var(--primary);
      box-shadow: 0 0 0 3px rgba(34, 183, 255, 0.2);
    }

    /* Left Panel: Space */
    .space-panel {
      background: radial-gradient(circle at 50% 35%, #18274c 0%, var(--space-bg) 85%);
      color: #ffffff;
      border-color: #24355a;
    }

    .space-panel.active {
      border-color: var(--primary);
    }

    .stars-bg {
      position: absolute;
      inset: 0;
      pointer-events: none;
      background-image: 
        radial-gradient(1px 1px at 20px 30px, #ffffff, transparent),
        radial-gradient(1.5px 1.5px at 70px 20px, #b0d4ff, transparent),
        radial-gradient(1px 1px at 120px 60px, #ffffff, transparent),
        radial-gradient(1.5px 1.5px at 30px 120px, #ffffff, transparent),
        radial-gradient(1px 1px at 100px 140px, #8ec5ff, transparent),
        radial-gradient(1px 1px at 140px 25px, #ffffff, transparent);
    }

    /* Visual Stages */
    .visual-stage {
      height: 150px;
      width: 100%;
      display: flex;
      align-items: center;
      justify-content: center;
      position: relative;
      margin-bottom: 6px;
      z-index: 1;
    }

    /* SVG Artwork */
    .art-svg {
      width: 100%;
      height: 100%;
      max-height: 145px;
      overflow: visible;
    }

    /* Labels */
    .panel-title {
      font-size: 15px;
      font-weight: 800;
      margin-bottom: 2px;
      z-index: 1;
    }

    .space-panel .panel-title {
      color: #ffffff;
    }

    .model-panel .panel-title {
      color: var(--text);
    }

    .panel-subtitle {
      font-size: 12px;
      font-weight: 600;
      z-index: 1;
    }

    .space-panel .panel-subtitle {
      color: #94a3b8;
    }

    .model-panel .panel-subtitle {
      color: var(--muted);
    }

    /* Connecting Ribbon */
    .bridge-pill {
      background: #ffffff;
      border: 2px solid var(--primary);
      border-radius: 999px;
      padding: 6px 14px;
      font-size: 12px;
      font-weight: 700;
      color: var(--text);
      display: flex;
      align-items: center;
      justify-content: center;
      gap: 6px;
      box-shadow: 0 3px 10px rgba(34, 183, 255, 0.15);
      text-align: center;
    }

    .bridge-pill .arrow-icon {
      color: var(--primary);
      font-weight: 900;
      font-size: 14px;
    }

    /* Interactive Globe Spin */
    .interactive-globe {
      cursor: grab;
      transform-origin: 100px 72px;
      transition: transform 0.5s cubic-bezier(0.2, 0.8, 0.3, 1);
    }

    .interactive-globe:active {
      cursor: grabbing;
    }

    /* Button Controls */
    .control-row {
      display: flex;
      justify-content: center;
      gap: 8px;
      width: 100%;
    }

    .mode-btn {
      background: #ffffff;
      border: 1.5px solid var(--border);
      border-radius: 999px;
      padding: 6px 14px;
      font-size: 12px;
      font-weight: 600;
      color: var(--text);
      cursor: pointer;
      display: inline-flex;
      align-items: center;
      gap: 5px;
      transition: background 0.2s, border-color 0.2s;
    }

    .mode-btn.active {
      background: var(--primary-light);
      border-color: var(--primary);
      color: #0369a1;
      font-weight: 700;
    }

    @media (max-width: 420px) {
      .panel-title { font-size: 14px; }
      .panel-subtitle { font-size: 11px; }
      .bridge-pill { font-size: 11px; padding: 5px 10px; }
      .visual-stage { height: 130px; }
    }
  </style>
</head>
<body>

  <div class="container">
    
    <div class="compare-wrap">
      
      
      <div class="panel space-panel active" id="realPanel">
        <div class="stars-bg"></div>
        <div class="visual-stage">
          <svg class="art-svg" viewBox="0 0 200 150">
            <defs>
              <radialGradient id="earthGlow" cx="50%" cy="50%" r="50%">
                <stop offset="70%" stop-color="#22b7ff" stop-opacity="0.35" />
                <stop offset="100%" stop-color="#22b7ff" stop-opacity="0" />
              </radialGradient>
              <linearGradient id="oceanGrad" x1="0" y1="0" x2="1" y2="1">
                <stop offset="0%" stop-color="#38bdf8" />
                <stop offset="100%" stop-color="#0284c7" />
              </linearGradient>
              <clipPath id="earthClip">
                <circle cx="100" cy="75" r="54" />
              </clipPath>
            </defs>

            
            <circle cx="100" cy="75" r="66" fill="url(#earthGlow)" />

            
            <circle cx="100" cy="75" r="54" fill="url(#oceanGrad)" stroke="#7dd3fc" stroke-width="1.5" />

            
            <g clip-path="url(#earthClip)">
              
              <path d="M70 45 Q85 35 105 42 Q115 50 110 65 Q95 72 82 60 Z" fill="#4ade80" opacity="0.95" />
              <path d="M120 50 Q135 45 145 60 Q140 75 125 78 Q118 68 120 50 Z" fill="#4ade80" opacity="0.95" />
              <path d="M85 85 Q100 80 108 95 Q102 115 90 120 Q80 108 85 85 Z" fill="#22c55e" opacity="0.95" />
              <path d="M130 90 Q145 92 142 108 Q132 112 126 102 Z" fill="#4ade80" opacity="0.95" />
              
              <path d="M60 65 Q80 58 105 66 Q120 70 145 62" stroke="#ffffff" stroke-width="4" stroke-linecap="round" fill="none" opacity="0.5" />
              <path d="M75 98 Q100 92 125 100" stroke="#ffffff" stroke-width="3.5" stroke-linecap="round" fill="none" opacity="0.45" />
            </g>

            
            <g transform="translate(100, 138)">
              <rect x="-46" y="-10" width="92" height="20" rx="10" fill="rgba(15, 23, 42, 0.85)" stroke="#38bdf8" stroke-width="1" />
              <text text-anchor="middle" y="3.5" fill="#bae6fd" font-size="10" font-weight="700">12,740 km wide</text>
            </g>
          </svg>
        </div>
        <div class="panel-title">Real Earth</div>
        <div class="panel-subtitle">Huge & far away!</div>
      </div>

      
      <div class="panel model-panel active" id="modelPanel">
        <div class="visual-stage">
          <svg class="art-svg" viewBox="0 0 200 150">
            
            <ellipse cx="100" cy="138" rx="34" ry="7" fill="#cbd5e1" />
            <path d="M100 135 L100 120" stroke="#64748b" stroke-width="5" stroke-linecap="round" />
            
            
            <path d="M100 24 A 48 48 0 0 0 100 120" fill="none" stroke="#94a3b8" stroke-width="4.5" stroke-linecap="round" />

            
            <g id="globeGroup" class="interactive-globe">
              <clipPath id="miniGlobeClip">
                <circle cx="100" cy="72" r="36" />
              </clipPath>

              
              <circle cx="100" cy="72" r="36" fill="#38bdf8" stroke="#0284c7" stroke-width="1.5" />
              
              
              <g clip-path="url(#miniGlobeClip)" id="globeContinents">
                <circle cx="88" cy="60" r="14" fill="#4ade80" />
                <circle cx="116" cy="64" r="11" fill="#4ade80" />
                <circle cx="95" cy="86" r="13" fill="#22c55e" />
                
                <ellipse cx="100" cy="72" rx="36" ry="10" fill="none" stroke="#bae6fd" stroke-width="1" stroke-dasharray="2 3" />
              </g>
              
              <circle cx="100" cy="72" r="36" fill="url(#miniGlobeClip)" />
              <path d="M100 36 A 36 36 0 0 1 136 72 A 36 36 0 0 1 100 108" fill="none" stroke="rgba(255,255,255,0.4)" stroke-width="2" />
            </g>

            
            <circle cx="100" cy="36" r="3" fill="#64748b" />
            <circle cx="100" cy="108" r="3" fill="#64748b" />

            
            <g transform="translate(142, 66)">
              
              <circle cx="0" cy="0" r="14" fill="#22b7ff" />
              <text x="0" y="4" text-anchor="middle" font-size="12" fill="#ffffff">🖐️</text>
            </g>

            
            <g transform="translate(56, 72)">
              <text font-size="11" fill="#0284c7" font-weight="800">↻</text>
            </g>

            
            <g transform="translate(100, 140)">
              <rect x="-38" y="-9" width="76" height="18" rx="9" fill="#e2e8f0" stroke="#cbd5e1" stroke-width="1" />
              <text text-anchor="middle" y="3.5" fill="#334155" font-size="10" font-weight="700">30 cm wide</text>
            </g>
          </svg>
        </div>
        <div class="panel-title">Globe Model</div>
        <div class="panel-subtitle">Small & easy to study!</div>
      </div>

    </div>

    
    <div class="bridge-pill">
      <span>A model stands in for the real thing</span>
      <span class="arrow-icon">➔</span>
    </div>

    
    <div class="control-row">
      <button class="mode-btn active" id="btnBoth" onclick="setMode('both')">Compare Both</button>
      <button class="mode-btn" id="btnSpin" onclick="spinGlobe()">Spin Model ↻</button>
    </div>
  </div>

  <script>
    let currentRotation = 0;
    const globeGroup = document.getElementById('globeGroup');

    function spinGlobe() {
      currentRotation += 180;
      globeGroup.style.transform = `rotate(${currentRotation}deg)`;
    }

    // Tap globe directly to spin
    globeGroup.addEventListener('click', spinGlobe);

    function setMode(mode) {
      document.querySelectorAll('.mode-btn').forEach(btn => btn.classList.remove('active'));
      const realP = document.getElementById('realPanel');
      const modelP = document.getElementById('modelPanel');
      
      if (mode === 'both') {
        document.getElementById('btnBoth').classList.add('active');
        realP.classList.add('active');
        modelP.classList.add('active');
      }
    }
  </script>
</body>
</html>

OGS.2.SEP.6

Aligned learning resources

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