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  <title>Alexander Fleming's Discovery - Petri Dish Diagram</title>
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</head>
<body>

<div class="diagram-wrap">
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      <text x="106" y="24" text-anchor="end" class="label-title">MOLD SPOT</text>
      <text x="106" y="37" text-anchor="end" class="label-sub" fill="#15803d">Penicillium notatum</text>
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    <g id="lbl-clear" class="zone-focus">
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      <text x="324" y="270" class="label-sub" fill="#ca8a04">Living Staphylococcus</text>
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  </svg>

  
  <div id="info-panel" class="info-panel">
    In 1928, Alexander Fleming observed a mold preventing bacterial growth, discovering the first antibiotic: penicillin.
  </div>

  
  <div class="nav-tabs">
    <button class="tab-btn active" onclick="setFocus('all', this)">Show All</button>
    <button class="tab-btn" onclick="setFocus('mold', this)">1. Mold Spot</button>
    <button class="tab-btn" onclick="setFocus('clear', this)">2. Clear Zone</button>
    <button class="tab-btn" onclick="setFocus('bacteria', this)">3. Bacterial Colony</button>
  </div>
</div>

<script>
  const descriptions = {
    all: "In 1928, Alexander Fleming observed a mold preventing bacterial growth, discovering the first antibiotic: penicillin.",
    mold: "Penicillium mold: Secretes penicillin, a natural substance toxic to certain bacterial cell walls.",
    clear: "Clear Zone (Zone of Inhibition): Antibiotic diffused through the agar, destroying and preventing bacteria from growing.",
    bacteria: "Bacterial Colony (Staphylococcus): Thrives far away from the mold, but cannot survive near the penicillin."
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    const infoPanel = document.getElementById('info-panel');

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    infoPanel.textContent = descriptions[mode] || descriptions.all;

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      lblMold.classList.add('dimmed');
      lblClear.classList.add('dimmed');
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  }
</script>

</body>
</html>

How Scientific Discoveries Solve Everyday Problems

<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <meta name="aspect-ratio" content="4:3">
  <style>
    * {
      box-sizing: border-box;
      margin: 0;
      padding: 0;
    }

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

    .comic-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 10px;
      width: 100%;
      max-width: 620px;
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    .comic-card {
      background: #ffffff;
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      flex-direction: column;
      align-items: center;
      justify-content: space-between;
      box-shadow: 0 3px 8px rgba(0, 0, 0, 0.04);
      cursor: pointer;
      transition: border-color 0.25s ease, box-shadow 0.25s ease, transform 0.25s ease;
      position: relative;
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    .comic-card.active {
      border-color: #22b7ff;
      box-shadow: 0 6px 18px rgba(34, 183, 255, 0.22);
      transform: translateY(-2px);
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    .step-badge {
      font-size: 12px;
      font-weight: 800;
      color: #0284c7;
      background: #e0f2fe;
      padding: 3px 8px;
      border-radius: 12px;
      margin-bottom: 6px;
      letter-spacing: 0.5px;
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    .comic-card.active .step-badge {
      background: #22b7ff;
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    .art-container {
      width: 100%;
      height: 110px;
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      align-items: center;
      justify-content: center;
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    svg {
      width: 100%;
      height: 100%;
      max-height: 110px;
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    .label {
      font-size: 14px;
      font-weight: 700;
      color: #1e2945;
      text-align: center;
      margin-top: 6px;
      line-height: 1.2;
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    .controls {
      display: flex;
      align-items: center;
      gap: 8px;
      margin-top: 14px;
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    .btn {
      background: #ffffff;
      border: 1.5px solid #cbd5e1;
      border-radius: 20px;
      padding: 6px 14px;
      font-size: 13px;
      font-weight: 700;
      color: #1e2945;
      cursor: pointer;
      display: flex;
      align-items: center;
      gap: 5px;
      user-select: none;
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    .btn:active {
      background: #f1f5f9;
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      background: #22b7ff;
      border-color: #22b7ff;
      color: #ffffff;
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      50% { transform: scale(1.06); }
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    @keyframes float-y {
      0%, 100% { transform: translateY(0); }
      50% { transform: translateY(-4px); }
    }

    @keyframes shield-glow {
      0%, 100% { filter: drop-shadow(0 0 2px rgba(34,183,255,0.4)); }
      50% { filter: drop-shadow(0 0 6px rgba(34,183,255,0.8)); }
    }

    .active .pulse-el {
      animation: pulse-subtle 2s infinite ease-in-out;
      transform-origin: center;
    }

    .active .float-el {
      animation: float-y 2.2s infinite ease-in-out;
    }

    .active .glow-el {
      animation: shield-glow 2s infinite ease-in-out;
    }
  </style>
</head>
<body>

  <div class="comic-grid">
    
    <div class="comic-card active" onclick="setStep(0)" id="card-0">
      <span class="step-badge">1. PRACTICE</span>
      <div class="art-container">
        <svg viewBox="0 0 100 100">
          
          <path d="M 12 18 L 32 38" stroke="#94a3b8" stroke-width="4" stroke-linecap="round" />
          <rect x="24" y="24" width="16" height="10" rx="3" transform="rotate(45 28 28)" fill="#38bdf8" opacity="0.8" />
          <circle cx="36" cy="42" r="2.5" fill="#38bdf8" />
          
          
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            <circle cx="65" cy="38" r="4" fill="#a7f3d0" />
            <circle cx="85" cy="58" r="4" fill="#a7f3d0" />
            <circle cx="65" cy="78" r="4" fill="#a7f3d0" />
            <circle cx="45" cy="58" r="4" fill="#a7f3d0" />
            <circle cx="51" cy="44" r="3.5" fill="#a7f3d0" />
            <circle cx="79" cy="44" r="3.5" fill="#a7f3d0" />
            <circle cx="79" cy="72" r="3.5" fill="#a7f3d0" />
            <circle cx="51" cy="72" r="3.5" fill="#a7f3d0" />

            
            <circle cx="65" cy="58" r="18" fill="#34d399" stroke="#059669" stroke-width="2" stroke-dasharray="3 2" />

            
            
            <path d="M 57 55 Q 60 52 63 55" stroke="#065f46" stroke-width="2" fill="none" stroke-linecap="round" />
            
            <path d="M 67 55 Q 70 52 73 55" stroke="#065f46" stroke-width="2" fill="none" stroke-linecap="round" />
            
            <path d="M 61 63 Q 65 65 69 63" stroke="#065f46" stroke-width="1.8" fill="none" stroke-linecap="round" />
            
            <text x="82" y="36" font-size="11" font-weight="900" fill="#059669">z</text>
          </g>
        </svg>
      </div>
      <div class="label">Weakened<br>Germ</div>
    </div>

    
    <div class="comic-card" onclick="setStep(1)" id="card-1">
      <span class="step-badge">2. MEMORY</span>
      <div class="art-container">
        <svg viewBox="0 0 100 100">
          
          <g class="glow-el">
            <path d="M 28 22 Q 46 16 52 14 Q 58 16 76 22 C 76 50 56 68 52 72 C 48 68 28 50 28 22 Z" 
                  fill="#0284c7" stroke="#38bdf8" stroke-width="2.5" />
            
            <circle cx="45" cy="36" r="2.5" fill="#ffffff" />
            <circle cx="59" cy="36" r="2.5" fill="#ffffff" />
            <path d="M 46 44 Q 52 50 58 44" stroke="#ffffff" stroke-width="2.2" fill="none" stroke-linecap="round" />
          </g>

          
          
          <g class="float-el" transform="translate(10, 48) scale(0.9)">
            <path d="M 12 18 L 12 28 M 12 18 L 6 10 M 12 18 L 18 10" 
                  stroke="#2563eb" stroke-width="3" stroke-linecap="round" stroke-linejoin="round" />
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          <g class="float-el" transform="translate(68, 48) scale(0.9)">
            <path d="M 12 18 L 12 28 M 12 18 L 6 10 M 12 18 L 18 10" 
                  stroke="#2563eb" stroke-width="3" stroke-linecap="round" stroke-linejoin="round" />
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          <g class="float-el" transform="translate(66, 6) scale(0.8)">
            <path d="M 12 18 L 12 28 M 12 18 L 6 10 M 12 18 L 18 10" 
                  stroke="#2563eb" stroke-width="3.2" stroke-linecap="round" stroke-linejoin="round" />
          </g>
        </svg>
      </div>
      <div class="label">Antibodies<br>Made</div>
    </div>

    
    <div class="comic-card" onclick="setStep(2)" id="card-2">
      <span class="step-badge">3. DEFENSE</span>
      <div class="art-container">
        <svg viewBox="0 0 100 100">
          
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            <polygon points="50,22 46,30 54,30" fill="#ef4444" />
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            <polygon points="70,70 62,66 66,62" fill="#ef4444" />

            
            <circle cx="50" cy="50" r="17" fill="#f87171" stroke="#dc2626" stroke-width="2" />

            
            <path d="M 42 45 L 47 49 M 47 45 L 42 49" stroke="#7f1d1d" stroke-width="2" stroke-linecap="round" />
            <path d="M 53 45 L 58 49 M 58 45 L 53 49" stroke="#7f1d1d" stroke-width="2" stroke-linecap="round" />
            <ellipse cx="50" cy="56" rx="4" ry="2" fill="#7f1d1d" />
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          <g transform="translate(38, 2) scale(0.9)">
            <path d="M 13 22 L 13 10 M 13 22 L 7 30 M 13 22 L 19 30" 
                  stroke="#0284c7" stroke-width="3" stroke-linecap="round" stroke-linejoin="round" />
          </g>
          
          <g transform="translate(38, 66) scale(0.9)">
            <path d="M 13 14 L 13 26 M 13 14 L 7 6 M 13 14 L 19 6" 
                  stroke="#0284c7" stroke-width="3" stroke-linecap="round" stroke-linejoin="round" />
          </g>
          
          <g transform="translate(4, 38) scale(0.9)">
            <path d="M 22 13 L 10 13 M 22 13 L 30 7 M 22 13 L 30 19" 
                  stroke="#0284c7" stroke-width="3" stroke-linecap="round" stroke-linejoin="round" />
          </g>
          
          <g transform="translate(68, 38) scale(0.9)">
            <path d="M 14 13 L 26 13 M 14 13 L 6 7 M 14 13 L 6 19" 
                  stroke="#0284c7" stroke-width="3" stroke-linecap="round" stroke-linejoin="round" />
          </g>

          
          <circle cx="50" cy="50" r="32" fill="none" stroke="#38bdf8" stroke-width="2" stroke-dasharray="5 3" opacity="0.85" />
        </svg>
      </div>
      <div class="label">Germ<br>Blocked!</div>
    </div>
  </div>

  <div class="controls">
    <button class="btn primary" id="playBtn" onclick="togglePlay()">
      <span id="playIcon">⏸</span> Auto-Play
    </button>
  </div>

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

    function updateView() {
      for (let i = 0; i < 3; i++) {
        const card = document.getElementById(`card-${i}`);
        if (i === currentStep) {
          card.classList.add('active');
        } else {
          card.classList.remove('active');
        }
      }
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    function setStep(index) {
      currentStep = index;
      updateView();
    }

    function nextStep() {
      currentStep = (currentStep + 1) % 3;
      updateView();
    }

    function togglePlay() {
      isPlaying = !isPlaying;
      const playIcon = document.getElementById('playIcon');
      const playBtn = document.getElementById('playBtn');

      if (isPlaying) {
        playIcon.textContent = '⏸';
        playBtn.classList.add('primary');
        startTimer();
      } else {
        playIcon.textContent = '▶';
        playBtn.classList.remove('primary');
        clearInterval(timer);
      }
    }

    function startTimer() {
      clearInterval(timer);
      timer = setInterval(() => {
        if (isPlaying) {
          nextStep();
        }
      }, 3000);
    }

    // Initialize auto-play
    startTimer();
  </script>
</body>
</html>

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

    .flow-grid {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 8px;
      width: 100%;
      max-width: 640px;
    }

    .step-card {
      background: #ffffff;
      border: 1.5px solid #e6e6e6;
      border-radius: 12px;
      padding: 10px 6px;
      display: flex;
      flex-direction: column;
      align-items: center;
      cursor: pointer;
      position: relative;
      transition: border-color 0.3s ease, box-shadow 0.3s ease;
      user-select: none;
    }

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

    .step-num {
      font-size: 11px;
      font-weight: 700;
      color: #6b7280;
      margin-bottom: 6px;
      display: flex;
      align-items: center;
      gap: 3px;
    }

    .step-card.active .step-num {
      color: #0284c7;
    }

    .graphic-box {
      width: 100%;
      height: 110px;
      background: #f8fafc;
      border-radius: 8px;
      border: 1px solid #edf2f7;
      position: relative;
      overflow: hidden;
      display: flex;
      align-items: center;
      justify-content: center;
    }

    .step-label {
      font-size: 12px;
      font-weight: 700;
      color: #1e2945;
      margin-top: 8px;
      text-align: center;
      line-height: 1.2;
    }

    /* Card 1: River Water */
    .water-murky {
      position: absolute;
      inset: 0;
      background: linear-gradient(180deg, #d4b896 0%, #b89368 100%);
      opacity: 0.9;
    }
    .particle {
      position: absolute;
      border-radius: 50%;
      background: #5c3a21;
    }

    /* Card 2: Gravel Filter */
    .filter-stage {
      position: absolute;
      inset: 0;
      display: flex;
      flex-direction: column;
    }
    .water-semi-murky {
      flex: 1;
      background: #cbb497;
    }
    .gravel-bed {
      height: 38px;
      background: #9ca3af;
      display: flex;
      flex-wrap: wrap;
      align-items: center;
      justify-content: center;
      gap: 3px;
      padding: 3px;
      border-top: 2px dashed #4b5563;
      border-bottom: 2px dashed #4b5563;
    }
    .gravel-stone {
      width: 8px;
      height: 8px;
      border-radius: 40%;
      background: #4b5563;
    }
    .water-clearer-1 {
      flex: 1;
      background: #bee3f8;
    }

    /* Card 3: Sand Filter */
    .sand-bed {
      height: 34px;
      background: #e2d9b8;
      border-top: 1px dashed #ca8a04;
      border-bottom: 1px dashed #ca8a04;
      display: flex;
      flex-wrap: wrap;
      align-items: center;
      justify-content: space-around;
      padding: 2px;
    }
    .sand-grain {
      width: 3px;
      height: 3px;
      border-radius: 50%;
      background: #a16207;
      margin: 1px;
    }
    .water-clearer-2 {
      flex: 1;
      background: #e0f2fe;
    }

    /* Card 4: Disinfection */
    .water-pure {
      position: absolute;
      inset: 0;
      background: linear-gradient(180deg, #bae6fd 0%, #38bdf8 100%);
      display: flex;
      flex-direction: column;
      align-items: center;
      justify-content: center;
    }
    .chlorine-drop {
      position: absolute;
      top: 6px;
      font-size: 16px;
      animation: drop 2.2s infinite ease-in;
    }
    .germ {
      font-size: 13px;
      transition: opacity 0.5s ease;
    }
    .germ-dead {
      opacity: 0.15;
      filter: grayscale(1);
    }
    .sparkle {
      position: absolute;
      font-size: 12px;
      color: #ffffff;
      animation: pulse 1.8s infinite ease-in-out;
    }

    /* Floating / trapped items */
    .leaf { font-size: 13px; position: absolute; }
    .twig {
      position: absolute;
      width: 14px;
      height: 3px;
      background: #5c3a21;
      transform: rotate(25deg);
      border-radius: 2px;
    }

    @keyframes drop {
      0% { transform: translateY(0); opacity: 1; }
      50% { transform: translateY(32px); opacity: 1; }
      70% { transform: translateY(38px); opacity: 0; }
      100% { transform: translateY(0); opacity: 0; }
    }

    @keyframes pulse {
      0%, 100% { opacity: 0.2; transform: scale(0.8); }
      50% { opacity: 1; transform: scale(1.1); }
    }

    /* Controls bar */
    .controls {
      display: flex;
      align-items: center;
      gap: 12px;
      margin-top: 14px;
    }
    .btn {
      background: #ffffff;
      border: 1px solid #e6e6e6;
      border-radius: 20px;
      padding: 6px 14px;
      font-size: 13px;
      font-weight: 600;
      color: #1e2945;
      cursor: pointer;
      display: flex;
      align-items: center;
      gap: 5px;
    }
    .btn-primary {
      background: #22b7ff;
      border-color: #22b7ff;
      color: #ffffff;
    }

    @media (max-width: 480px) {
      .flow-grid {
        grid-template-columns: repeat(2, 1fr);
        gap: 8px;
      }
      .graphic-box {
        height: 90px;
      }
    }
  </style>
</head>
<body>

  <div class="flow-grid">
    
    <div class="step-card active" onclick="setStep(0)" id="card-0">
      <div class="step-num"><span>1</span> River Source</div>
      <div class="graphic-box">
        <div class="water-murky"></div>
        <span class="leaf" style="top:18%; left:20%;">🍂</span>
        <span class="leaf" style="top:55%; right:22%;">🌿</span>
        <div class="twig" style="top:40%; left:30%;"></div>
        <div class="particle" style="width:5px; height:5px; top:25%; left:65%;"></div>
        <div class="particle" style="width:7px; height:7px; top:70%; left:45%;"></div>
        <div class="particle" style="width:4px; height:4px; top:80%; left:20%;"></div>
        <span class="germ" style="position:absolute; top:45%; left:65%;">🦠</span>
      </div>
      <div class="step-label">Murky Water</div>
    </div>

    
    <div class="step-card" onclick="setStep(1)" id="card-1">
      <div class="step-num"><span>2</span> Coarse Filter</div>
      <div class="graphic-box">
        <div class="filter-stage">
          <div class="water-semi-murky" style="position:relative;">
            <span class="leaf" style="top:15%; left:25%;">🍂</span>
            <div class="twig" style="top:35%; right:20%;"></div>
          </div>
          <div class="gravel-bed">
            <div class="gravel-stone"></div>
            <div class="gravel-stone" style="width:11px; height:10px;"></div>
            <div class="gravel-stone"></div>
            <div class="gravel-stone" style="width:10px; height:9px;"></div>
            <div class="gravel-stone"></div>
            <div class="gravel-stone"></div>
            <div class="gravel-stone"></div>
          </div>
          <div class="water-clearer-1" style="position:relative;">
            <div class="particle" style="width:4px; height:4px; top:30%; left:30%;"></div>
            <div class="particle" style="width:3px; height:3px; top:50%; left:65%;"></div>
            <span class="germ" style="position:absolute; top:20%; left:70%; font-size:10px;">🦠</span>
          </div>
        </div>
      </div>
      <div class="step-label">Gravel Bed</div>
    </div>

    
    <div class="step-card" onclick="setStep(2)" id="card-2">
      <div class="step-num"><span>3</span> Fine Filter</div>
      <div class="graphic-box">
        <div class="filter-stage">
          <div class="water-clearer-1" style="position:relative;">
            <div class="particle" style="width:4px; height:4px; top:35%; left:25%;"></div>
            <div class="particle" style="width:3px; height:3px; top:45%; left:60%;"></div>
          </div>
          <div class="sand-bed">
            <div class="sand-grain"></div><div class="sand-grain"></div>
            <div class="sand-grain"></div><div class="sand-grain"></div>
            <div class="sand-grain"></div><div class="sand-grain"></div>
            <div class="sand-grain"></div><div class="sand-grain"></div>
            <div class="sand-grain"></div><div class="sand-grain"></div>
            <div class="sand-grain"></div><div class="sand-grain"></div>
          </div>
          <div class="water-clearer-2" style="position:relative;">
            <span class="germ" style="position:absolute; top:25%; left:45%; font-size:11px;">🦠</span>
          </div>
        </div>
      </div>
      <div class="step-label">Sand Bed</div>
    </div>

    
    <div class="step-card" onclick="setStep(3)" id="card-3">
      <div class="step-num"><span>4</span> Disinfection</div>
      <div class="graphic-box">
        <div class="water-pure">
          <div class="chlorine-drop">💧</div>
          <span class="germ germ-dead" style="position:absolute; top:50%; left:25%;">🦠</span>
          <span class="sparkle" style="top:25%; right:22%;">✦</span>
          <span class="sparkle" style="bottom:22%; left:30%;">✦</span>
          <span style="font-size:24px; position:absolute; bottom:6px;">🥛</span>
        </div>
      </div>
      <div class="step-label">Clean & Safe</div>
    </div>
  </div>

  <div class="controls">
    <button class="btn" id="prevBtn" onclick="prevStep()">← Prev</button>
    <button class="btn btn-primary" id="playBtn" onclick="toggleAuto()">▶ Auto Flow</button>
    <button class="btn" id="nextBtn" onclick="nextStep()">Next →</button>
  </div>

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

    function updateCards() {
      for (let i = 0; i < 4; i++) {
        const card = document.getElementById(`card-${i}`);
        if (i === currentStep) {
          card.classList.add('active');
        } else {
          card.classList.remove('active');
        }
      }
    }

    function setStep(index) {
      currentStep = index;
      updateCards();
    }

    function nextStep() {
      currentStep = (currentStep + 1) % 4;
      updateCards();
    }

    function prevStep() {
      currentStep = (currentStep - 1 + 4) % 4;
      updateCards();
    }

    function toggleAuto() {
      const btn = document.getElementById('playBtn');
      if (timer) {
        clearInterval(timer);
        timer = null;
        btn.textContent = '▶ Auto Flow';
      } else {
        nextStep();
        timer = setInterval(nextStep, 3000);
        btn.textContent = '⏸ Pause';
      }
    }
  </script>
</body>
</html>

OGS.4.HSS.6

Aligned learning resources

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