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    .val-dist { color: #047857; font-weight: 700; }
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    .val-joule { color: #0284c7; font-weight: 700; }
    .val-kilo { color: #6b21a8; font-weight: 700; }

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      background: #dbeafe;
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      color: #065f46;
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      background: #f3e8ff;
      color: #6b21a8;
      border: 1px solid #d8b4fe;
    }

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      line-height: 1;
      height: 14px;
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        padding: 2px 5px;
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</head>
<body>

  
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    <button class="step-btn active" id="btn0">1. Formula</button>
    <button class="step-btn" id="btn1">2. Substitute</button>
    <button class="step-btn" id="btn2">3. Convert</button>
    <button class="play-btn" id="playBtn" title="Play/Pause" aria-label="Toggle auto-play">⏸</button>
  </div>

  
  <div class="steps-container">
    
    
    <div class="calc-card active" id="card0">
      <div class="card-header">
        <span class="card-title">1. Formula</span>
        <div class="badges-row">
          <span class="badge badge-force"><var>F</var> = Force</span>
          <span class="badge badge-dist"><var>s</var> = Distance</span>
        </div>
      </div>
      <div class="math-row">
        <var>W</var> <span class="op">=</span> <var>F</var> <span class="op">&times;</span> <var>s</var>
      </div>
    </div>

    <div class="connector">↓</div>

    
    <div class="calc-card" id="card1">
      <div class="card-header">
        <span class="card-title">2. Substitution</span>
        <div class="badges-row">
          <span class="badge badge-force">450 N</span>
          <span class="badge badge-dist">4 m</span>
        </div>
      </div>
      <div class="math-row">
        <var>W</var> <span class="op">=</span> 
        <span class="val-force">450<span class="unit">N</span></span> 
        <span class="op">&times;</span> 
        <span class="val-dist">4<span class="unit">m</span></span> 
        <span class="op">=</span> 
        <span class="val-nm">1800<span class="unit">N&middot;m</span></span>
      </div>
    </div>

    <div class="connector">↓</div>

    
    <div class="calc-card" id="card2">
      <div class="card-header">
        <span class="card-title">3. Equivalence &amp; Conversion</span>
        <div class="badges-row">
          <span class="badge badge-equiv">1 N&middot;m = 1 J</span>
          <span class="badge badge-kilo">&divide; 1000 &rarr; kJ</span>
        </div>
      </div>
      <div class="math-row">
        <span class="val-nm">1800<span class="unit">N&middot;m</span></span> 
        <span class="op">=</span> 
        <span class="val-joule">1800<span class="unit">J</span></span> 
        <span class="op">=</span> 
        <span class="val-kilo">1.8<span class="unit">kJ</span></span>
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    </div>

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Equivalence of Joules and Newton-Metres in Mechanical Work

<!DOCTYPE html>
<html lang="en">
<head>
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    * {
      box-sizing: border-box;
      margin: 0;
      padding: 0;
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    body {
      font-family: system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
      background: transparent;
      color: #0f172a;
      padding: 8px;
      margin: 0;
      display: flex;
      justify-content: center;
      align-items: center;
    }

    .grid-container {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 16px;
      width: 100%;
      max-width: 620px;
    }

    @media (max-width: 480px) {
      .grid-container {
        grid-template-columns: 1fr;
        gap: 12px;
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    .panel {
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      flex-direction: column;
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      text-align: center;
      gap: 6px;
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    .badge {
      display: inline-block;
      font-size: 11px;
      font-weight: 700;
      text-transform: uppercase;
      letter-spacing: 0.5px;
      padding: 3px 10px;
      border-radius: 12px;
    }

    .badge-linear {
      background: #e0f2fe;
      color: #0369a1;
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    .badge-rotational {
      background: #fce7f3;
      color: #be185d;
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      font-size: 15px;
      font-weight: 700;
      color: #0f172a;
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    .canvas-wrap {
      width: 100%;
      height: 135px;
      position: relative;
      background: #f8fafc;
      border-radius: 8px;
      overflow: hidden;
      display: flex;
      align-items: center;
      justify-content: center;
    }

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

    .result-box {
      width: 100%;
      padding: 8px 10px;
      border-radius: 8px;
      display: flex;
      flex-direction: column;
      gap: 2px;
      align-items: center;
    }

    .result-work {
      background: #f0fdf4;
      color: #14532d;
    }

    .result-torque {
      background: #fff1f2;
      color: #881337;
    }

    .formula {
      font-size: 15px;
      font-weight: 800;
      letter-spacing: 0.2px;
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    .valid-eq {
      color: #15803d;
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      font-weight: 700;
      display: inline-flex;
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      gap: 4px;
    }

    .invalid-eq {
      color: #dc2626;
      font-size: 12px;
      font-weight: 700;
      display: inline-flex;
      align-items: center;
      gap: 4px;
    }

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      text-decoration-thickness: 2px;
      color: #dc2626;
    }

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      transform-origin: 35px 84px;
      animation: rotateWrench 6s cubic-bezier(0.4, 0, 0.2, 1) infinite;
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      0%, 30% { transform: translateX(0px); }
      50%, 80% { transform: translateX(70px); }
      100% { transform: translateX(0px); }
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      50%, 80% { transform: translateX(70px); }
      100% { transform: translateX(0px); }
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      0%, 30% { transform: rotate(0deg); }
      50%, 80% { transform: rotate(-24deg); }
      100% { transform: rotate(0deg); }
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</head>
<body>

  <div class="grid-container">
    
    <div class="panel">
      <span class="badge badge-linear">Linear Motion</span>
      <div class="panel-title">Work Done</div>

      <div class="canvas-wrap">
        <svg viewBox="0 0 200 135" aria-label="Work Done Diagram">
          <defs>
            <marker id="arr-d" viewBox="0 0 6 6" refX="5" refY="3" markerWidth="4" markerHeight="4" orient="auto">
              <path d="M 0 1 L 5 3 L 0 5 z" fill="#334155" />
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            </marker>
          </defs>

          
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          <line x1="43" y1="102" x2="113" y2="102" stroke="#475569" stroke-width="1.5" marker-end="url(#arr-d)" marker-start="url(#arr-d-start)" />
          <text x="78" y="120" font-size="10" fill="#334155" text-anchor="middle" font-weight="700">Distance (d)</text>

          
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            <text x="43" y="72" font-size="10.5" font-weight="800" fill="#0369a1" text-anchor="middle">1 kg</text>
          </g>

          
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          </g>
        </svg>
      </div>

      <div class="result-box result-work">
        <div class="formula">1 N·m = 1 J</div>
        <div class="valid-eq">✓ Energy Transferred</div>
        <div class="sub-note">Scalar quantity</div>
      </div>
    </div>

    
    <div class="panel">
      <span class="badge badge-rotational">Rotational Effect</span>
      <div class="panel-title">Torque / Moment</div>

      <div class="canvas-wrap">
        <svg viewBox="0 0 200 135" aria-label="Torque Diagram">
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              <path d="M 0 1 L 5 3 L 0 5 z" fill="#be185d" />
            </marker>
          </defs>

          
          <path d="M 145 80 A 110 110 0 0 0 132 36" fill="none" stroke="#f472b6" stroke-width="1.5" stroke-dasharray="3 3" />

          
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            <rect x="35" y="80" width="105" height="8" rx="4" fill="#cbd5e1" stroke="#64748b" stroke-width="1.5" />
            <circle cx="35" cy="84" r="7" fill="#94a3b8" stroke="#475569" stroke-width="1.5" />
            <circle cx="35" cy="84" r="2.5" fill="#1e293b" />

            
            <line x1="135" y1="80" x2="135" y2="40" stroke="#be185d" stroke-width="3" marker-end="url(#arr-torque-force)" />
            <text x="145" y="55" font-size="11" font-weight="800" fill="#be185d">F</text>

            
            <path d="M 127 80 L 127 72 L 135 72" fill="none" stroke="#be185d" stroke-width="1.5" />
          </g>

          
          <circle cx="35" cy="84" r="3.5" fill="#334155" />
          <text x="35" y="120" font-size="10" fill="#334155" text-anchor="middle" font-weight="700">Pivot</text>

          
          <line x1="42" y1="102" x2="135" y2="102" stroke="#475569" stroke-width="1.5" marker-end="url(#arr-d2)" marker-start="url(#arr-d2-start)" />
          <text x="88" y="120" font-size="10" fill="#334155" text-anchor="middle" font-weight="700">Radius (r)</text>
        </svg>
      </div>

      <div class="result-box result-torque">
        <div class="formula">1 N·m <span style="font-size:12px; font-weight: 700; color:#475569;">ONLY</span></div>
        <div class="invalid-eq">✕ <span class="strike-text">1 Joule (J)</span></div>
        <div class="sub-note">Turning effect, not energy</div>
      </div>
    </div>
  </div>

</body>
</html>

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<html lang="en">
<head>
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  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>Work Done: Joules and Newton-Metres</title>
  <style>
    * {
      box-sizing: border-box;
      margin: 0;
      padding: 0;
    }

    body {
      font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
      background: #f8f9fa;
      color: #1e2945;
      display: flex;
      flex-direction: column;
      align-items: center;
      justify-content: center;
      min-height: 100vh;
      padding: 12px 16px;
    }

    .main-stage {
      width: 100%;
      max-width: 480px;
      display: flex;
      flex-direction: column;
      gap: 16px;
    }

    /* Simulation Container */
    .sim-area {
      width: 100%;
      padding: 10px 4px 6px;
    }

    .track-area {
      position: relative;
      height: 125px;
      width: 100%;
    }

    /* Floor & Track */
    .floor-line {
      position: absolute;
      top: 68px;
      left: 14%;
      right: 14%;
      height: 2px;
      background: #cbd5e1;
    }

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      left: 14%;
      top: 68px;
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      background: #22b7ff;
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      transition: width 1.1s cubic-bezier(0.4, 0, 0.2, 1);
      z-index: 1;
    }

    .tick {
      position: absolute;
      top: 64px;
      width: 2px;
      height: 10px;
      background: #94a3b8;
    }

    .tick-start {
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    .tick-end {
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    .tick-label {
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    .tick-start-label {
      left: 14%;
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    .tick-end-label {
      left: 86%;
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      background: #22b7ff;
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    .dimension-line-left::before {
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      z-index: 2;
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      border-radius: 8px;
      display: flex;
      align-items: center;
      justify-content: center;
      font-size: 20px;
      box-shadow: 0 2px 8px rgba(34, 183, 255, 0.2);
      user-select: none;
      flex-shrink: 0;
    }

    /* Formula Banner */
    .formula-section {
      width: 100%;
      text-align: center;
      display: flex;
      flex-direction: column;
      gap: 8px;
      padding: 4px 0;
    }

    .formula-title {
      font-size: 13px;
      font-weight: 700;
      color: #64748b;
      letter-spacing: 0.5px;
      text-transform: uppercase;
    }

    .formula-row {
      display: flex;
      align-items: center;
      justify-content: center;
      flex-wrap: wrap;
      gap: 6px;
      font-size: clamp(12px, 3.4vw, 15px);
      font-weight: 700;
      color: #1e2945;
    }

    .formula-chunk {
      display: inline-flex;
      align-items: center;
      gap: 4px;
      white-space: nowrap;
    }

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      padding: 4px 8px;
      border-radius: 6px;
      background: #e2e8f0;
      color: #334155;
    }

    .val-box.force {
      background: #e0f2fe;
      color: #0284c7;
      border: 1px solid #bae6fd;
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    .val-box.dist {
      background: #e0f2fe;
      color: #0284c7;
      border: 1px solid #bae6fd;
    }

    .val-box.work {
      background: #22b7ff;
      color: #ffffff;
      border: 1px solid #0284c7;
      transition: background 0.3s ease;
    }

    /* Controls */
    .controls {
      display: flex;
      justify-content: center;
      padding-top: 4px;
    }

    .action-btn {
      background: #22b7ff;
      color: #ffffff;
      border: none;
      font-size: 14px;
      font-weight: 600;
      padding: 9px 22px;
      border-radius: 8px;
      cursor: pointer;
      display: flex;
      align-items: center;
      gap: 6px;
      transition: opacity 0.2s ease, background-color 0.2s ease;
    }

    .action-btn:hover {
      background: #0ea5e9;
    }

    .action-btn:active {
      opacity: 0.9;
    }
  </style>
</head>
<body>

  <div class="main-stage">
    
    
    <div class="sim-area">
      <div class="track-area" id="trackArea">
        <div class="floor-line"></div>
        <div class="distance-fill" id="distFill"></div>

        <div class="tick tick-start"></div>
        <div class="tick-label tick-start-label">0 m</div>

        <div class="tick tick-end"></div>
        <div class="tick-label tick-end-label">1 m</div>

        
        <div class="mover-group" id="moverGroup">
          <div class="force-arrow-container">
            <span class="force-badge">Force: 1 N</span>
            <span class="force-arrow">➔</span>
          </div>
          <div class="box">📦</div>
        </div>

        
        <div class="distance-dimension">
          <div class="dimension-line-left"></div>
          <div class="distance-tag">Distance: 1 m</div>
          <div class="dimension-line-right"></div>
        </div>
      </div>
    </div>

    
    <div class="formula-section">
      <div class="formula-title">Work Done = Force × Distance</div>
      <div class="formula-row">
        <span class="formula-chunk">
          <span class="val-box force">1 N</span>
          <span>×</span>
          <span class="val-box dist">1 m</span>
        </span>
        <span>=</span>
        <span class="formula-chunk">
          <span class="val-box">1 N·m</span>
        </span>
        <span>=</span>
        <span class="formula-chunk">
          <span class="val-box work" id="workResult">1 J (Joule)</span>
        </span>
      </div>
    </div>

    
    <div class="controls">
      <button class="action-btn" id="toggleBtn" aria-label="Animate box pushing 1 metre">
        <span id="btnIcon">▶</span>
        <span id="btnText">Push 1 Metre</span>
      </button>
    </div>

  </div>

  <script>
    const moverGroup = document.getElementById('moverGroup');
    const distFill = document.getElementById('distFill');
    const toggleBtn = document.getElementById('toggleBtn');
    const btnIcon = document.getElementById('btnIcon');
    const btnText = document.getElementById('btnText');
    const trackArea = document.getElementById('trackArea');

    let isPushed = false;

    function calculateTravelDistance() {
      const trackWidth = trackArea.clientWidth;
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      const span = trackWidth * 0.72 - 42;
      return Math.max(span, 0);
    }

    function applyState() {
      const travel = calculateTravelDistance();
      if (isPushed) {
        moverGroup.style.transform = `translateX(${travel}px)`;
        distFill.style.width = '72%';
        btnIcon.textContent = '↺';
        btnText.textContent = 'Reset';
      } else {
        moverGroup.style.transform = 'translateX(0px)';
        distFill.style.width = '0%';
        btnIcon.textContent = '▶';
        btnText.textContent = 'Push 1 Metre';
      }
    }

    function togglePush() {
      isPushed = !isPushed;
      applyState();
    }

    toggleBtn.addEventListener('click', togglePush);

    window.addEventListener('resize', () => {
      if (isPushed) {
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        distFill.style.transition = 'none';
        applyState();
        requestAnimationFrame(() => {
          moverGroup.style.transition = 'transform 1.1s cubic-bezier(0.4, 0, 0.2, 1)';
          distFill.style.transition = 'width 1.1s cubic-bezier(0.4, 0, 0.2, 1)';
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      }
    });

    // Auto-demonstrate after brief initial pause
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      if (!isPushed) {
        togglePush();
      }
    }, 700);
  </script>
</body>
</html>

<!DOCTYPE html>
<html lang="en">
<head>
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  <meta name="aspect-ratio" content="1:1">
  <title>Dimensional Analysis: Joules and Newton-Metres</title>
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      box-shadow: 0 2px 6px rgba(34, 183, 255, 0.3);
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      color: #334155;
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      align-items: center;
      justify-content: center;
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    /* Flowchart Container */
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      display: grid;
      grid-template-columns: 1fr auto 1fr;
      gap: 8px;
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      max-width: 400px;
      align-items: center;
      position: relative;
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    .column {
      display: flex;
      flex-direction: column;
      gap: 8px;
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    .card-box {
      background: #f8fafc;
      border: 1.5px solid #e2e8f0;
      border-radius: 8px;
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    .card-box.active {
      opacity: 1;
      border-color: #38bdf8;
      background: #f0f9ff;
      box-shadow: 0 3px 8px rgba(56, 189, 248, 0.15);
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    .card-box.target.active {
      border-color: #10b981;
      background: #ecfdf5;
      box-shadow: 0 0 12px rgba(16, 185, 129, 0.35);
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    .tag {
      font-size: 11px;
      font-weight: 700;
      text-transform: uppercase;
      letter-spacing: 0.5px;
      color: #64748b;
      margin-bottom: 2px;
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    .card-box.active .tag {
      color: #0284c7;
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    .card-box.target.active .tag {
      color: #059669;
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    .math {
      font-family: "Cambria Math", "Times New Roman", serif;
      font-size: 15px;
      font-weight: 600;
      color: #0f172a;
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      color: #0284c7;
      font-weight: 700;
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    .green-hl {
      color: #059669;
      font-weight: 700;
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    /* Central Bridge */
    .bridge {
      display: flex;
      flex-direction: column;
      align-items: center;
      justify-content: flex-end;
      height: 100%;
      padding-bottom: 14px;
    }
    .equal-sign {
      width: 32px;
      height: 32px;
      border-radius: 50%;
      background: #f1f5f9;
      border: 1.5px solid #cbd5e1;
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      font-size: 18px;
      font-weight: 700;
      color: #94a3b8;
      transition: all 0.4s ease;
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    .equal-sign.glow {
      background: #10b981;
      border-color: #059669;
      color: #ffffff;
      transform: scale(1.15);
      box-shadow: 0 0 16px rgba(16, 185, 129, 0.6);
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    /* Bottom Summary */
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      width: 100%;
      max-width: 380px;
      text-align: center;
      padding: 8px 10px;
      border-radius: 8px;
      font-size: 13px;
      font-weight: 600;
      background: #f8fafc;
      border: 1px dashed #cbd5e1;
      color: #64748b;
      margin-top: 6px;
      transition: all 0.3s ease;
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      background: #ecfdf5;
      border: 1.5px solid #10b981;
      color: #065f46;
      box-shadow: 0 2px 10px rgba(16, 185, 129, 0.2);
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    .arrow-down {
      font-size: 11px;
      color: #94a3b8;
      margin: -4px 0;
      text-align: center;
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  </style>
</head>
<body>

  
  <div class="controls">
    <button class="step-btn active" onclick="setStep(0)">1. Unit</button>
    <button class="step-btn" onclick="setStep(1)">2. Expand</button>
    <button class="step-btn" onclick="setStep(2)">3. Multiply</button>
    <button class="step-btn" onclick="setStep(3)">4. Equivalence</button>
    <button class="play-btn" id="playToggle" onclick="togglePlay()" title="Toggle Auto-Play">⏸</button>
  </div>

  
  <div class="flowchart">
    
    <div class="column">
      
      <div class="card-box" id="l1">
        <div class="tag">Work (F · d)</div>
        <div class="math"><span class="highlight">N</span> · m</div>
      </div>
      <div class="arrow-down">↓</div>
      
      <div class="card-box" id="l2">
        <div class="tag">Force = m · a</div>
        <div class="math">(kg·m/s²) · m</div>
      </div>
      <div class="arrow-down">↓</div>
      
      <div class="card-box target" id="l3">
        <div class="tag">SI Base</div>
        <div class="math green-hl">kg·m²/s²</div>
      </div>
    </div>

    
    <div class="bridge">
      <div class="equal-sign" id="eqSign">=</div>
    </div>

    
    <div class="column">
      
      <div class="card-box" id="r1">
        <div class="tag">Energy (½mv²)</div>
        <div class="math"><span class="highlight">J</span> (Joule)</div>
      </div>
      <div class="arrow-down">↓</div>
      
      <div class="card-box" id="r2">
        <div class="tag">Mass · Speed²</div>
        <div class="math">kg · (m/s)²</div>
      </div>
      <div class="arrow-down">↓</div>
      
      <div class="card-box target" id="r3">
        <div class="tag">SI Base</div>
        <div class="math green-hl">kg·m²/s²</div>
      </div>
    </div>
  </div>

  
  <div class="summary-badge" id="summary">
    1 N·m = 1 J = 1 kg·m²/s²
  </div>

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</body>
</html>

UK-GCSE-SCIENCE-PHYS-FOR-03-02

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