<!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 {
      width: 100%;
      background: #f8f9fa;
      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: 10px;
    }

    .microscope-container {
      position: relative;
      width: 100%;
      max-width: 380px;
      aspect-ratio: 1 / 1;
      display: flex;
      align-items: center;
      justify-content: center;
    }

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

    /* Interactive button controls */
    .controls {
      display: flex;
      flex-wrap: wrap;
      gap: 6px;
      justify-content: center;
      margin-top: 10px;
      max-width: 380px;
    }

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      border: 1.5px solid #cbd5e1;
      color: #1e2945;
      padding: 5px 10px;
      border-radius: 16px;
      font-size: 13px;
      font-weight: 600;
      cursor: pointer;
      user-select: none;
      transition: all 0.25s ease;
    }

    .btn-tag:hover {
      border-color: #22b7ff;
    }

    .btn-tag.active {
      background: #1e2945;
      color: #ffffff;
      border-color: #1e2945;
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    /* SVG structural highlights */
    .highlight-wall .cell-wall { stroke: #4d7c0f !important; stroke-width: 5px !important; }
    .highlight-membrane .cell-membrane { stroke: #0284c7 !important; stroke-width: 3.5px !important; }
    .highlight-nucleus .cell-nucleus { fill: #b91c1c !important; transform: scale(1.25); transform-box: fill-box; transform-origin: center; }
    .highlight-cytoplasm .cell-cytoplasm { fill: #fde047 !important; fill-opacity: 0.7 !important; }

    /* Transitions */
    .cell-wall, .cell-membrane, .cell-nucleus, .cell-cytoplasm {
      transition: all 0.3s ease;
    }

    .label-text {
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      font-weight: 700;
      fill: #1e2945;
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    .callout-line {
      stroke: #1e2945;
      stroke-width: 1.5;
      stroke-dasharray: 3, 3;
    }

    .callout-dot {
      fill: #1e2945;
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</head>
<body>

  <div class="microscope-container" id="scopeContainer">
    <svg viewBox="0 0 400 400">
      <defs>
        
        <clipPath id="fov-clip">
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        <pattern id="cytoplasm-pattern" width="8" height="8" patternUnits="userSpaceOnUse">
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        <radialGradient id="light-grad" cx="45%" cy="45%" r="65%">
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        <rect x="110" y="80" width="150" height="75" fill="#fef9c3" />
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        <ellipse class="cell-nucleus" cx="225" cy="100" rx="9" ry="8.5" fill="#9a3412" />
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        <rect x="260" y="80" width="150" height="75" fill="#fef9c3" />
        <rect class="cell-cytoplasm" x="262" y="82" width="146" height="71" fill="url(#cytoplasm-pattern)" />
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        <rect class="cell-membrane" x="263" y="83" width="144" height="69" fill="none" stroke="#ca8a04" stroke-width="1.5" />
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        <rect x="20" y="155" width="140" height="80" fill="#fef9c3" />
        <rect class="cell-cytoplasm" x="22" y="157" width="136" height="76" fill="url(#cytoplasm-pattern)" />
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        <rect class="cell-wall" x="20" y="155" width="140" height="80" fill="none" stroke="#84732b" stroke-width="3.5" />
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        <rect x="160" y="155" width="155" height="80" fill="#fef9c3" />
        
        <rect class="cell-cytoplasm" x="162" y="157" width="151" height="76" fill="url(#cytoplasm-pattern)" />
        
        <rect x="180" y="168" width="115" height="54" rx="8" fill="#fffbeb" fill-opacity="0.75" stroke="#fef08a" stroke-width="1" />
        
        <rect class="cell-membrane" id="targetMembrane" x="163.5" y="158.5" width="148" height="73" fill="none" stroke="#ca8a04" stroke-width="1.8" />
        
        <rect class="cell-wall" id="targetWall" x="160" y="155" width="155" height="80" fill="none" stroke="#71672c" stroke-width="4" />
        
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        <rect class="cell-cytoplasm" x="317" y="157" width="126" height="76" fill="url(#cytoplasm-pattern)" />
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        <rect x="-10" y="235" width="120" height="75" fill="#fef9c3" />
        <rect class="cell-cytoplasm" x="-8" y="237" width="116" height="71" fill="url(#cytoplasm-pattern)" />
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        <rect x="110" y="235" width="145" height="75" fill="#fef9c3" />
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      <circle cx="200" cy="200" r="166" fill="none" stroke="#0f172a" stroke-width="1" />

      
      
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      <circle class="callout-dot" cx="160" cy="155" r="3.5" />
      <rect x="18" y="52" width="76" height="24" rx="12" fill="#ffffff" stroke="#cbd5e1" />
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      <circle class="callout-dot" cx="164" cy="210" r="3.5" />
      <rect x="8" y="318" width="110" height="24" rx="12" fill="#ffffff" stroke="#cbd5e1" />
      <text class="label-text" x="63" y="334" text-anchor="middle">Cell Membrane</text>

      
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      <circle class="callout-dot" cx="215" cy="165" r="3.5" />
      <rect x="298" y="52" width="90" height="24" rx="12" fill="#ffffff" stroke="#cbd5e1" />
      <text class="label-text" x="343" y="68" text-anchor="middle">Cytoplasm</text>

      
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      <circle class="callout-dot" cx="272" cy="208" r="3.5" />
      <rect x="308" y="318" width="76" height="24" rx="12" fill="#ffffff" stroke="#cbd5e1" />
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      <rect x="165" y="338" width="70" height="20" rx="10" fill="#1e2945" fill-opacity="0.85" />
      <text x="200" y="352" text-anchor="middle" fill="#ffffff" font-size="11" font-weight="700" letter-spacing="0.5">100×</text>
    </svg>
  </div>

  
  <div class="controls">
    <button class="btn-tag active" data-type="all">All</button>
    <button class="btn-tag" data-type="wall">Cell Wall</button>
    <button class="btn-tag" data-type="membrane">Cell Membrane</button>
    <button class="btn-tag" data-type="cytoplasm">Cytoplasm</button>
    <button class="btn-tag" data-type="nucleus">Nucleus</button>
  </div>

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    const container = document.getElementById('scopeContainer');
    const buttons = document.querySelectorAll('.btn-tag');

    buttons.forEach(btn => {
      btn.addEventListener('click', () => {
        buttons.forEach(b => b.classList.remove('active'));
        btn.classList.add('active');

        // Reset highlight classes
        container.classList.remove('highlight-wall', 'highlight-membrane', 'highlight-cytoplasm', 'highlight-nucleus');

        const type = btn.getAttribute('data-type');
        if (type === 'wall') container.classList.add('highlight-wall');
        else if (type === 'membrane') container.classList.add('highlight-membrane');
        else if (type === 'cytoplasm') container.classList.add('highlight-cytoplasm');
        else if (type === 'nucleus') container.classList.add('highlight-nucleus');
      });
    });
  </script>
</body>
</html>

Microscopic Observation of Plant and Animal Cells

<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <meta name="aspect-ratio" content="4:3">
  <style>
    * { box-sizing: border-box; margin: 0; padding: 0; }
    body {
      background-color: #f8f9fa;
      font-family: system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
      color: #1e2945;
      width: 100%;
      min-height: 100%;
      display: flex;
      flex-direction: column;
      align-items: center;
      padding: 12px;
    }

    .nav-bar {
      display: flex;
      gap: 6px;
      width: 100%;
      max-width: 440px;
      margin-bottom: 12px;
    }

    .step-btn {
      flex: 1;
      padding: 8px 4px;
      background: #ffffff;
      border: 1px solid #e6e6e6;
      border-radius: 8px;
      color: #6b7280;
      font-size: 13px;
      font-weight: 600;
      cursor: pointer;
      text-align: center;
      transition: all 0.25s ease;
    }

    .step-btn.active {
      background: #1e2945;
      color: #ffffff;
      border-color: #1e2945;
    }

    .stage-container {
      position: relative;
      width: 100%;
      max-width: 440px;
      height: 280px;
      background: #ffffff;
      border: 1px solid #e6e6e6;
      border-radius: 12px;
      overflow: hidden;
    }

    .stage {
      position: absolute;
      inset: 0;
      display: flex;
      flex-direction: column;
      align-items: center;
      justify-content: center;
      opacity: 0;
      pointer-events: none;
      transition: opacity 0.3s ease;
      padding: 12px;
    }

    .stage.active {
      opacity: 1;
      pointer-events: auto;
    }

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

    .badge {
      display: inline-flex;
      align-items: center;
      gap: 4px;
      font-size: 13px;
      font-weight: 600;
      padding: 4px 8px;
      border-radius: 6px;
    }

    .badge-success {
      background: #ecfdf5;
      color: #059669;
      border: 1px solid #a7f3d0;
    }

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

    .controls {
      display: flex;
      align-items: center;
      justify-content: space-between;
      width: 100%;
      max-width: 440px;
      margin-top: 10px;
    }

    .ctrl-btn {
      background: #ffffff;
      border: 1px solid #e6e6e6;
      color: #1e2945;
      border-radius: 6px;
      padding: 6px 14px;
      font-size: 13px;
      font-weight: 600;
      cursor: pointer;
    }

    .dots {
      display: flex;
      gap: 6px;
    }

    .dot {
      width: 8px;
      height: 8px;
      border-radius: 50%;
      background: #e6e6e6;
      cursor: pointer;
      transition: background 0.2s ease;
    }

    .dot.active {
      background: #22b7ff;
    }
  </style>
</head>
<body>

  <div class="nav-bar">
    <button class="step-btn active" onclick="setStep(0)">1. Specimen & Drop</button>
    <button class="step-btn" onclick="setStep(1)">2. 45° Angle</button>
    <button class="step-btn" onclick="setStep(2)">3. Lower Flat</button>
  </div>

  <div class="stage-container">
    
    <div class="stage active" id="stage-0">
      <svg viewBox="0 0 400 240">
        
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        <ellipse cx="200" cy="144" rx="35" ry="14" fill="#22b7ff" fill-opacity="0.5" stroke="#0ea5e9" stroke-width="1.5"/>
        <ellipse cx="192" cy="138" rx="8" ry="3" fill="#ffffff" opacity="0.7"/>

        
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        <text x="200" y="24" text-anchor="middle" fill="#1e2945" font-size="13" font-weight="700">Water Drop</text>
        <text x="200" y="195" text-anchor="middle" fill="#1e2945" font-size="13" font-weight="700">Glass Slide & Specimen</text>
      </svg>
    </div>

    
    <div class="stage" id="stage-1">
      <svg viewBox="0 0 400 240">
        
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        <rect x="175" y="146" width="50" height="4" fill="#86efac" stroke="#4ade80" stroke-width="1"/>

        
        <path d="M165 150 C185 142, 215 142, 235 150 Z" fill="#22b7ff" fill-opacity="0.55" stroke="#0ea5e9" stroke-width="1.5"/>

        
        <g transform="translate(165, 150) rotate(-45)">
          <rect x="0" y="-3" width="90" height="5" rx="1.5" fill="#e0f2fe" fill-opacity="0.8" stroke="#0284c7" stroke-width="1.5"/>
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        </g>

        
        <path d="M215 150 A50 50 0 0 0 200 115" fill="none" stroke="#22b7ff" stroke-width="2" stroke-dasharray="3,3"/>
        
        
        <path d="M245 105 L260 120 L245 135" fill="none" stroke="#1e2945" stroke-width="2" stroke-linecap="round" stroke-linejoin="round"/>
        
        
        <text x="218" y="132" fill="#0284c7" font-size="14" font-weight="700">45°</text>
        <text x="140" y="65" text-anchor="middle" fill="#1e2945" font-size="13" font-weight="700">Coverslip</text>
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        <text x="200" y="195" text-anchor="middle" fill="#1e2945" font-size="13" font-weight="700">Touch Edge of Water</text>
      </svg>
    </div>

    
    <div class="stage" id="stage-2">
      <svg viewBox="0 0 400 240">
        
        <rect x="30" y="45" width="200" height="18" rx="3" fill="#f0f9ff" stroke="#cbd5e1" stroke-width="1.5"/>
        
        
        <rect x="75" y="42" width="110" height="3" fill="#22b7ff" opacity="0.6"/>
        <rect x="110" y="43" width="40" height="2" fill="#86efac"/>
        
        
        <rect x="75" y="39" width="110" height="3" rx="1" fill="#e0f2fe" stroke="#0284c7" stroke-width="1.5"/>

        
        <rect x="55" y="85" width="150" height="120" rx="4" fill="#f8fafc" stroke="#cbd5e1" stroke-width="1.5"/>
        <rect x="75" y="95" width="110" height="100" rx="2" fill="#e0f2fe" fill-opacity="0.4" stroke="#0284c7" stroke-width="1.5"/>
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        <circle cx="68" cy="100" r="10" fill="#ecfdf5"/>
        <text x="68" y="104" text-anchor="middle" fill="#059669" font-size="12" font-weight="bold">✓</text>
        <text x="130" y="222" text-anchor="middle" fill="#059669" font-size="13" font-weight="700">No Bubbles</text>

        
        <rect x="250" y="45" width="125" height="160" rx="8" fill="#ffffff" stroke="#fecaca" stroke-width="1.5"/>
        <rect x="262" y="60" width="100" height="95" rx="2" fill="#fef2f2" stroke="#f87171" stroke-width="1"/>
        <rect x="287" y="88" width="50" height="38" fill="#86efac" opacity="0.6"/>
        
        
        <circle cx="282" cy="78" r="8" fill="#ffffff" stroke="#1e2945" stroke-width="2.5"/>
        <circle cx="335" cy="115" r="12" fill="#ffffff" stroke="#1e2945" stroke-width="3"/>
        <circle cx="305" cy="135" r="7" fill="#ffffff" stroke="#1e2945" stroke-width="2"/>
        
        <circle cx="260" cy="55" r="10" fill="#fee2e2"/>
        <text x="260" y="59" text-anchor="middle" fill="#dc2626" font-size="12" font-weight="bold">✗</text>
        <text x="312" y="185" text-anchor="middle" fill="#dc2626" font-size="13" font-weight="700">Trapped Bubbles</text>
      </svg>
    </div>
  </div>

  <div class="controls">
    <button class="ctrl-btn" onclick="prevStep()">◀ Back</button>
    <div class="dots">
      <div class="dot active" onclick="setStep(0)"></div>
      <div class="dot" onclick="setStep(1)"></div>
      <div class="dot" onclick="setStep(2)"></div>
    </div>
    <button class="ctrl-btn" onclick="nextStep()">Next ▶</button>
  </div>

  <script>
    let current = 0;
    const stages = document.querySelectorAll('.stage');
    const btns = document.querySelectorAll('.step-btn');
    const dots = document.querySelectorAll('.dot');
    let timer = null;

    function setStep(idx) {
      current = (idx + 3) % 3;
      stages.forEach((s, i) => s.classList.toggle('active', i === current));
      btns.forEach((b, i) => b.classList.toggle('active', i === current));
      dots.forEach((d, i) => d.classList.toggle('active', i === current));
      resetTimer();
    }

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

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

    function resetTimer() {
      if (timer) clearInterval(timer);
      timer = setInterval(() => {
        setStep(current + 1);
      }, 3500);
    }

    resetTimer();
  </script>
</body>
</html>

OGS.8.LS.1

Aligned learning resources

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