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  </style>
</head>
<body>

  <div class="header-bar">
    <div id="stepBadge" class="step-badge">STEP 1: SERIES PAIR</div>
    <div class="step-dots">
      <button class="dot active" onclick="goToStep(0)" aria-label="Step 1">1</button>
      <button class="dot" onclick="goToStep(1)" aria-label="Step 2">2</button>
      <button class="dot" onclick="goToStep(2)" aria-label="Step 3">3</button>
    </div>
  </div>

  <div class="stage-container">
    
    <div id="stage1" class="step-view active">
      <svg viewBox="0 0 540 220">
        
        <rect x="365" y="22" width="155" height="176" class="highlight-yellow" />
        <text x="442" y="14" class="tag-text" fill="#a16207">Series: R₄ + R₅</text>

        
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        <rect x="120" y="34" width="80" height="32" class="resistor-box" />
        <text x="160" y="50" class="resistor-text">R₁</text>

        
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        <text x="160" y="170" class="resistor-text">R₂</text>

        
        <rect x="274" y="85" width="32" height="60" class="resistor-box" />
        <text x="290" y="115" class="resistor-text">R₃</text>

        
        <rect x="390" y="34" width="80" height="32" class="resistor-box" />
        <text x="430" y="50" class="resistor-text">R₄</text>

        
        <rect x="479" y="100" width="32" height="60" class="resistor-box" />
        <text x="495" y="130" class="resistor-text">R₅</text>

        
        <circle cx="40" cy="50" r="11" class="terminal-dot" />
        <text x="40" y="50" class="terminal-label">A</text>

        <circle cx="40" cy="170" r="11" class="terminal-dot" />
        <text x="40" y="170" class="terminal-label">B</text>
      </svg>
    </div>

    
    <div id="stage2" class="step-view">
      <svg viewBox="0 0 540 220">
        
        <rect x="258" y="32" width="220" height="156" class="highlight-green" />
        <text x="368" y="20" class="tag-text" fill="#15803d">Parallel: R₃ ∥ R₄₅</text>

        
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        <rect x="120" y="34" width="80" height="32" class="resistor-box" />
        <text x="160" y="50" class="resistor-text">R₁</text>

        
        <rect x="120" y="154" width="80" height="32" class="resistor-box" />
        <text x="160" y="170" class="resistor-text">R₂</text>

        
        <rect x="274" y="85" width="32" height="60" class="resistor-box" />
        <text x="290" y="115" class="resistor-text">R₃</text>

        
        <rect x="420" y="85" width="40" height="60" class="resistor-box" fill="#fef9c3" />
        <text x="440" y="115" class="resistor-text" font-size="13">R₄₅</text>

        
        <circle cx="40" cy="50" r="11" class="terminal-dot" />
        <text x="40" y="50" class="terminal-label">A</text>

        <circle cx="40" cy="170" r="11" class="terminal-dot" />
        <text x="40" y="170" class="terminal-label">B</text>
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    </div>

    
    <div id="stage3" class="step-view">
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        <rect x="160" y="52" width="220" height="116" class="highlight-blue" />
        <text x="270" y="36" class="tag-text" fill="#0369a1">Equivalent Resistance</text>

        
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        <text x="270" y="110" class="resistor-text" font-size="18" fill="#0369a1">R_eq</text>

        
        <circle cx="40" cy="110" r="11" class="terminal-dot" />
        <text x="40" y="110" class="terminal-label">A</text>

        <circle cx="500" cy="110" r="11" class="terminal-dot" />
        <text x="500" y="110" class="terminal-label">B</text>
      </svg>
    </div>
  </div>

  <div class="controls">
    <button class="btn" onclick="resetDiagram()">↺ Reset</button>
    <button class="btn" onclick="prevStep()">◀ Prev</button>
    <button id="nextBtn" class="btn btn-primary" onclick="nextStep()">Next Step ▶</button>
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</body>
</html>

Equivalent Resistance in Combination Circuits

<!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>
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      box-sizing: border-box;
      margin: 0;
      padding: 0;
      user-select: none;
      -webkit-user-select: none;
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    body {
      font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
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      color: #1e2945;
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      background: #f1f5f9;
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      padding: 6px 12px;
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      color: #475569;
      cursor: pointer;
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      background: #0284c7;
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    svg {
      width: 100%;
      height: auto;
      max-height: 340px;
      overflow: visible;
    }

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</head>
<body>

  
  <div class="controls">
    <button class="step-btn active" onclick="setStep(0)">1. Ladder</button>
    <button class="step-btn" onclick="setStep(1)">2. R₄ + R₅</button>
    <button class="step-btn" onclick="setStep(2)">3. + R₃</button>
    <button class="step-btn" onclick="setStep(3)">4. ∥ R₂</button>
    <button class="step-btn" onclick="setStep(4)">5. R_eq</button>
  </div>

  
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    <svg viewBox="0 0 620 310">
      
      
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      <line x1="50" y1="250" x2="490" y2="250" class="wire" />

      
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      <line id="wire-CE" x1="250" y1="60" x2="310" y2="60" class="wire" />
      <line id="wire-Etop" x1="400" y1="60" x2="490" y2="60" class="wire" />

      
      <line id="wire-R2-top" x1="250" y1="60" x2="250" y2="105" class="wire" />
      <line id="wire-R2-bot" x1="250" y1="205" x2="250" y2="250" class="wire" />

      
      <line id="wire-R4-top" x1="490" y1="60" x2="490" y2="85" class="wire" />
      <line id="wire-R45-mid" x1="490" y1="145" x2="490" y2="165" class="wire" />
      <line id="wire-R5-bot" x1="490" y1="225" x2="490" y2="250" class="wire" />

      

      
      <g id="grp-r1">
        <rect x="100" y="38" width="90" height="44" class="resistor-box" />
        <text x="145" y="53" class="res-name">R₁</text>
        <text x="145" y="71" class="res-val">2 Ω</text>
      </g>

      
      <g id="grp-r2">
        <rect x="210" y="105" width="80" height="100" class="resistor-box" />
        <text x="250" y="145" class="res-name">R₂</text>
        <text x="250" y="168" class="res-val">12 Ω</text>
      </g>

      
      <g id="grp-r3">
        <rect x="310" y="38" width="90" height="44" class="resistor-box" />
        <text x="355" y="53" class="res-name">R₃</text>
        <text x="355" y="71" class="res-val">4 Ω</text>
      </g>

      
      <g id="grp-r4">
        <rect x="450" y="85" width="80" height="60" class="resistor-box" />
        <text x="490" y="107" class="res-name">R₄</text>
        <text x="490" y="127" class="res-val">10 Ω</text>
      </g>

      
      <g id="grp-r5">
        <rect x="450" y="165" width="80" height="60" class="resistor-box" />
        <text x="490" y="187" class="res-name">R₅</text>
        <text x="490" y="207" class="res-val">10 Ω</text>
      </g>

      
      
      <g id="grp-r45" style="display: none;">
        <rect x="445" y="105" width="90" height="100" class="resistor-box merged" />
        <text x="490" y="145" class="res-name">R₄₅</text>
        <text x="490" y="168" class="res-val" style="fill:#059669">20 Ω</text>
      </g>

      
      <g id="grp-r345" style="display: none;">
        <rect x="430" y="105" width="105" height="100" class="resistor-box merged" />
        <text x="482" y="145" class="res-name">R₃₄₅</text>
        <text x="482" y="168" class="res-val" style="fill:#059669">24 Ω</text>
      </g>

      
      <g id="grp-r2345" style="display: none;">
        <rect x="205" y="105" width="90" height="100" class="resistor-box merged" />
        <text x="250" y="145" class="res-name">R_p</text>
        <text x="250" y="168" class="res-val" style="fill:#059669">8 Ω</text>
      </g>

      
      <g id="grp-req" style="display: none;">
        <rect x="170" y="105" width="120" height="100" class="resistor-box merged" style="stroke:#0284c7; fill:#e0f2fe;" />
        <text x="230" y="145" class="res-name" style="font-size:16px;">R_eq</text>
        <text x="230" y="170" class="res-val" style="font-size:15px; font-weight:800;">10 Ω</text>
      </g>

      

      
      <circle cx="50" cy="60" r="14" fill="#4f46e5" />
      <text x="50" y="60" class="node-badge">A</text>

      
      <circle cx="50" cy="250" r="14" fill="#475569" />
      <text x="50" y="250" class="node-badge">B</text>

      
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        <text x="490" y="60" class="node-badge">E</text>
      </g>
    </svg>
  </div>

  
  <div id="formula" class="formula-bar">
    <span>Ladder Network: 5 Resistors</span>
  </div>

  <script>
    const formulas = [
      '<span>Ladder Network: 5 Resistors</span>',
      '<span>Right Branch Series: 10 + 10 = <span class="calc-tag">20 Ω</span></span>',
      '<span>Upper Series: 4 + 20 = <span class="calc-tag">24 Ω</span></span>',
      '<span>Parallel Pair: (12 × 24) / (12 + 24) = <span class="calc-tag">8 Ω</span></span>',
      '<span>Total Equivalent: 2 + 8 = <span class="calc-tag">10 Ω</span></span>'
    ];

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      const r5 = document.getElementById('grp-r5');
      const r45 = document.getElementById('grp-r45');
      const r345 = document.getElementById('grp-r345');
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        nodeD.style.display = '';
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        r4.style.display = 'none';
        r5.style.display = 'none';
        r45.style.display = '';
        r345.style.display = 'none';
        r2345.style.display = 'none';
        req.style.display = 'none';

        r45.querySelector('rect').classList.add('highlight');

        wireCE.style.display = '';
        wireEtop.style.display = '';
        wireR4top.style.display = '';
        wireR45mid.style.display = 'none';
        wireR5bot.style.display = '';
        wireR2top.style.display = '';
        wireR2bot.style.display = '';

        nodeC.style.display = '';
        nodeD.style.display = '';
        nodeE.style.display = '';
      }
      else if (step === 2) {
        // R3 + R45 in series -> R345 (24 ohm)
        r1.style.display = '';
        r2.style.display = '';
        r3.style.display = 'none';
        r4.style.display = 'none';
        r5.style.display = 'none';
        r45.style.display = 'none';
        r345.style.display = '';
        r2345.style.display = 'none';
        req.style.display = 'none';

        r345.querySelector('rect').classList.add('highlight');

        wireCE.style.display = '';
        wireEtop.style.display = 'none';
        wireR4top.style.display = '';
        wireR45mid.style.display = 'none';
        wireR5bot.style.display = '';
        wireR2top.style.display = '';
        wireR2bot.style.display = '';

        nodeC.style.display = '';
        nodeD.style.display = '';
        nodeE.style.display = 'none';
      }
      else if (step === 3) {
        // R2 || R345 -> R2345 (8 ohm)
        r1.style.display = '';
        r2.style.display = 'none';
        r3.style.display = 'none';
        r4.style.display = 'none';
        r5.style.display = 'none';
        r45.style.display = 'none';
        r345.style.display = 'none';
        r2345.style.display = '';
        req.style.display = 'none';

        r2345.querySelector('rect').classList.add('highlight');

        wireCE.style.display = 'none';
        wireEtop.style.display = 'none';
        wireR4top.style.display = 'none';
        wireR45mid.style.display = 'none';
        wireR5bot.style.display = 'none';
        wireR2top.style.display = '';
        wireR2bot.style.display = '';

        nodeC.style.display = '';
        nodeD.style.display = '';
        nodeE.style.display = 'none';
      }
      else if (step === 4) {
        // R1 + R2345 -> Req (10 ohm)
        r1.style.display = 'none';
        r2.style.display = 'none';
        r3.style.display = 'none';
        r4.style.display = 'none';
        r5.style.display = 'none';
        r45.style.display = 'none';
        r345.style.display = 'none';
        r2345.style.display = 'none';
        req.style.display = '';

        wireCE.style.display = 'none';
        wireEtop.style.display = 'none';
        wireR4top.style.display = 'none';
        wireR45mid.style.display = 'none';
        wireR5bot.style.display = 'none';
        wireR2top.style.display = 'none';
        wireR2bot.style.display = 'none';

        nodeC.style.display = 'none';
        nodeD.style.display = 'none';
        nodeE.style.display = 'none';
      }
    }
  </script>
</body>
</html>

<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <style>
    * { box-sizing: border-box; margin: 0; padding: 0; }
    body {
      width: 100%;
      min-height: 100%;
      font-family: system-ui, -apple-system, sans-serif;
      background: #f8fafc;
      color: #1e293b;
      padding: 10px;
      display: flex;
      flex-direction: column;
      align-items: center;
    }

    .header-title {
      font-size: 14px;
      font-weight: 700;
      color: #334155;
      text-transform: uppercase;
      letter-spacing: 0.5px;
      margin-bottom: 8px;
      text-align: center;
    }

    .grid {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 10px;
      width: 100%;
      max-width: 520px;
    }

    .panel {
      background: #ffffff;
      border: 1.5px solid #e2e8f0;
      border-radius: 8px;
      padding: 8px 6px 6px 6px;
      display: flex;
      flex-direction: column;
      align-items: center;
      position: relative;
    }

    .panel.invalid {
      border-color: #fecaca;
      background: #fffafa;
    }

    .panel.valid {
      border-color: #bbf7d0;
      background: #f0fdf4;
    }

    .badge {
      display: flex;
      align-items: center;
      justify-content: center;
      gap: 4px;
      font-size: 11px;
      font-weight: 700;
      line-height: 1.2;
      padding: 3px 8px;
      border-radius: 12px;
      margin-bottom: 4px;
      text-align: center;
    }

    .badge.invalid {
      background: #fee2e2;
      color: #dc2626;
    }

    .badge.valid {
      background: #dcfce7;
      color: #16a34a;
    }

    .panel-note {
      font-size: 10px;
      font-weight: 600;
      line-height: 1.2;
      text-align: center;
      margin-top: 4px;
      padding: 0 4px;
    }

    .panel.invalid .panel-note {
      color: #b91c1c;
    }

    .panel.valid .panel-note {
      color: #15803d;
    }

    svg {
      width: 100%;
      height: 95px;
      display: block;
    }

    .wire {
      stroke: #64748b;
      stroke-width: 2.5;
      fill: none;
      stroke-linecap: round;
      stroke-linejoin: round;
    }

    .wire-flow {
      stroke: #3b82f6;
      stroke-width: 3;
      stroke-dasharray: 6 6;
      animation: flow 3s linear infinite;
      fill: none;
      stroke-linecap: round;
      opacity: 0.85;
    }

    .resistor {
      fill: #ffffff;
      stroke: #1e293b;
      stroke-width: 2;
      rx: 2;
    }

    .resistor-invalid {
      fill: #fff1f2;
      stroke: #ef4444;
      stroke-width: 2;
      rx: 2;
    }

    .junction {
      fill: #ef4444;
      stroke: #ffffff;
      stroke-width: 1.5;
    }

    .node-top {
      fill: #2563eb;
      stroke: #ffffff;
      stroke-width: 1.5;
    }

    .node-bot {
      fill: #ea580c;
      stroke: #ffffff;
      stroke-width: 1.5;
    }

    .node-bar-top {
      stroke: #3b82f6;
      stroke-width: 4;
      stroke-linecap: round;
    }

    .node-bar-bot {
      stroke: #f97316;
      stroke-width: 4;
      stroke-linecap: round;
    }

    .label-text {
      font-size: 11px;
      font-weight: 700;
      fill: #1e293b;
      text-anchor: middle;
      dominant-baseline: central;
      pointer-events: none;
    }

    .warn-text {
      font-size: 9.5px;
      font-weight: 700;
      fill: #dc2626;
      text-anchor: middle;
      dominant-baseline: central;
    }

    .info-text {
      font-size: 9.5px;
      font-weight: 600;
      fill: #2563eb;
      text-anchor: middle;
      dominant-baseline: central;
    }

    @keyframes flow {
      from { stroke-dashoffset: 36; }
      to { stroke-dashoffset: 0; }
    }

    @media (max-width: 360px) {
      .grid {
        grid-template-columns: 1fr;
      }
      svg {
        height: 90px;
      }
    }
  </style>
</head>
<body>
  <div class="header-title">Circuit Analysis: Valid vs Invalid Combinations</div>
  
  <div class="grid">
    
    <div class="panel invalid">
      <div class="badge invalid">✕ NOT in Series</div>
      <svg viewBox="0 0 180 95">
        
        <path class="wire" d="M 10,38 L 170,38" />
        
        
        <path class="wire" d="M 90,38 L 90,74 L 140,74" stroke="#ef4444" stroke-width="2" stroke-dasharray="3 3" />
        <circle class="junction" cx="90" cy="38" r="4.5" />
        <text class="warn-text" x="135" y="62">Junction wire</text>
        <text class="warn-text" x="135" y="85">(draws current)</text>
        
        
        <rect class="resistor" x="36" y="28" width="34" height="20" />
        <text class="label-text" x="53" y="38">R₁</text>
        
        
        <rect class="resistor" x="110" y="28" width="34" height="20" />
        <text class="label-text" x="127" y="38">R₂</text>
      </svg>
      <div class="panel-note">Branch draws current away (I₁ ≠ I₂)</div>
    </div>

    
    <div class="panel valid">
      <div class="badge valid">✓ True Series</div>
      <svg viewBox="0 0 180 95">
        
        <path class="wire" d="M 10,48 L 170,48" />
        <path class="wire-flow" d="M 10,48 L 170,48" />
        
        
        <rect class="resistor" x="40" y="38" width="36" height="20" />
        <text class="label-text" x="58" y="48">R₁</text>
        
        
        <rect class="resistor" x="104" y="38" width="36" height="20" />
        <text class="label-text" x="122" y="48">R₂</text>
        
        <text class="info-text" x="90" y="18">Single unbranched loop</text>
      </svg>
      <div class="panel-note">Same current flows through all elements</div>
    </div>

    
    <div class="panel invalid">
      <div class="badge invalid">✕ NOT in Parallel</div>
      <svg viewBox="0 0 180 95">
        
        <path class="wire" d="M 15,16 L 165,16" />
        
        <path class="wire" d="M 15,82 L 165,82" />
        
        
        <path class="wire" d="M 50,16 L 50,82" />
        <rect class="resistor" x="35" y="38" width="30" height="18" />
        <text class="label-text" x="50" y="47">R₁</text>
        
        
        <path class="wire" d="M 130,16 L 130,82" stroke="#dc2626" />
        <rect class="resistor" x="115" y="24" width="30" height="16" />
        <text class="label-text" x="130" y="32">R₂</text>
        
        <rect class="resistor-invalid" x="115" y="52" width="30" height="16" />
        <text class="warn-text" x="130" y="60">R₃</text>
        <text class="warn-text" x="88" y="58">Extra R</text>
      </svg>
      <div class="panel-note">R₃ prevents direct shared node connection</div>
    </div>

    
    <div class="panel valid">
      <div class="badge valid">✓ True Parallel</div>
      <svg viewBox="0 0 180 95">
        
        <path class="node-bar-top" d="M 38,18 L 142,18" />
        
        <path class="node-bar-bot" d="M 38,80 L 142,80" />
        
        
        <path class="wire" d="M 15,18 L 38,18" />
        <path class="wire" d="M 142,80 L 165,80" />
        
        
        <path class="wire" d="M 58,18 L 58,80" />
        <rect class="resistor" x="43" y="38" width="30" height="20" />
        <text class="label-text" x="58" y="48">R₁</text>
        
        
        <path class="wire" d="M 122,18 L 122,80" />
        <rect class="resistor" x="107" y="38" width="30" height="20" />
        <text class="label-text" x="122" y="48">R₂</text>
        
        
        <circle class="node-top" cx="58" cy="18" r="4" />
        <circle class="node-top" cx="122" cy="18" r="4" />
        <circle class="node-bot" cx="58" cy="80" r="4" />
        <circle class="node-bot" cx="122" cy="80" r="4" />
      </svg>
      <div class="panel-note">Directly connected to common top & bottom nodes</div>
    </div>
  </div>
</body>
</html>

<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <style>
    * {
      box-sizing: border-box;
      margin: 0;
      padding: 0;
    }
    body {
      font-family: system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
      color: #1e2945;
      background: transparent;
      padding: 16px 12px;
      display: flex;
      justify-content: center;
      align-items: flex-start;
      min-height: auto;
    }
    .grid {
      display: grid;
      grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
      gap: 16px;
      width: 100%;
      max-width: 620px;
    }
    .circuit-card {
      background: #ffffff;
      border: 1px solid #e2e8f0;
      border-radius: 12px;
      padding: 16px 12px;
      display: flex;
      flex-direction: column;
      align-items: center;
    }
    .header {
      text-align: center;
      margin-bottom: 6px;
    }
    .title {
      font-size: 16px;
      font-weight: 700;
      color: #1e2945;
      line-height: 1.2;
    }
    .subtitle {
      font-size: 12px;
      font-weight: 600;
      color: #64748b;
      margin-top: 2px;
    }
    .schematic-wrap {
      width: 100%;
      max-width: 270px;
      height: 130px;
      display: flex;
      align-items: center;
      justify-content: center;
      margin: 4px 0;
    }
    svg {
      width: 100%;
      height: 100%;
      overflow: visible;
    }
    .wire-base {
      stroke: #cbd5e1;
      stroke-width: 3;
      fill: none;
      stroke-linecap: round;
      stroke-linejoin: round;
    }
    .current-flow {
      stroke: #2563eb;
      stroke-width: 2.5;
      fill: none;
      stroke-linecap: round;
      stroke-linejoin: round;
      stroke-dasharray: 6 10;
      animation: currentAnim 2.8s linear infinite;
    }
    @keyframes currentAnim {
      to {
        stroke-dashoffset: -32;
      }
    }
    .resistor-body {
      fill: #f8fafc;
      stroke: #1e2945;
      stroke-width: 2;
      rx: 4px;
    }
    .label {
      font-size: 12px;
      font-weight: 700;
      fill: #1e2945;
      text-anchor: middle;
      dominant-baseline: central;
    }
    .node-label {
      font-size: 11px;
      font-weight: 700;
      fill: #1e3a8a;
      text-anchor: middle;
    }
    .formula-badge {
      margin-top: 8px;
      padding: 6px 14px;
      background: #eff6ff;
      border: 1px solid #bfdbfe;
      border-radius: 8px;
      font-size: 13px;
      font-weight: 700;
      color: #1d4ed8;
      display: flex;
      align-items: center;
      justify-content: center;
      white-space: nowrap;
    }
    .frac {
      display: inline-flex;
      flex-direction: column;
      vertical-align: middle;
      text-align: center;
      padding: 0 3px;
      font-size: 12px;
      line-height: 1.1;
    }
    .frac-top {
      border-bottom: 1.5px solid #1d4ed8;
      padding-bottom: 1px;
    }
    .frac-bottom {
      padding-top: 1px;
    }
  </style>
</head>
<body>

  <div class="grid">
    
    <div class="circuit-card">
      <div class="header">
        <div class="title">Series</div>
        <div class="subtitle">Single Path</div>
      </div>
      
      <div class="schematic-wrap">
        <svg viewBox="0 0 260 130" aria-label="Series circuit schematic">
          
          <path class="wire-base" d="M 15 65 L 60 65 M 110 65 L 150 65 M 200 65 L 245 65" />
          
          
          <path class="current-flow" d="M 15 65 L 60 65 M 110 65 L 150 65 M 200 65 L 245 65" />
          
          
          <polygon points="34,61 42,65 34,69" fill="#2563eb" />
          <polygon points="128,61 136,65 128,69" fill="#2563eb" />
          <polygon points="220,61 228,65 220,69" fill="#2563eb" />

          
          <rect class="resistor-body" x="60" y="51" width="50" height="28" />
          <text class="label" x="85" y="65">R₁</text>

          
          <rect class="resistor-body" x="150" y="51" width="50" height="28" />
          <text class="label" x="175" y="65">R₂</text>

          
          <circle cx="15" cy="65" r="3.5" fill="#64748b" />
          <circle cx="245" cy="65" r="3.5" fill="#64748b" />
        </svg>
      </div>

      <div class="formula-badge">
        R<sub>eq</sub> = R₁ + R₂
      </div>
    </div>

    
    <div class="circuit-card">
      <div class="header">
        <div class="title">Parallel</div>
        <div class="subtitle">Split Paths</div>
      </div>

      <div class="schematic-wrap">
        <svg viewBox="0 0 260 130" aria-label="Parallel circuit schematic">
          
          <path class="wire-base" d="M 15 65 L 60 65" />
          <path class="wire-base" d="M 60 65 L 60 32 L 105 32 M 155 32 L 200 32 L 200 65" />
          <path class="wire-base" d="M 60 65 L 60 98 L 105 98 M 155 98 L 200 98 L 200 65" />
          <path class="wire-base" d="M 200 65 L 245 65" />

          
          <path class="current-flow" d="M 15 65 L 60 65" />
          <path class="current-flow" d="M 60 65 L 60 32 L 105 32 M 155 32 L 200 32 L 200 65" />
          <path class="current-flow" d="M 60 65 L 60 98 L 105 98 M 155 98 L 200 98 L 200 65" />
          <path class="current-flow" d="M 200 65 L 245 65" />

          
          <polygon points="34,61 42,65 34,69" fill="#2563eb" />
          <polygon points="176,28 184,32 176,36" fill="#2563eb" />
          <polygon points="176,94 184,98 176,102" fill="#2563eb" />
          <polygon points="220,61 228,65 220,69" fill="#2563eb" />

          
          <circle cx="60" cy="65" r="4.5" fill="#2563eb" />
          <text class="node-label" x="60" y="80">Node A</text>

          <circle cx="200" cy="65" r="4.5" fill="#2563eb" />
          <text class="node-label" x="200" y="80">Node B</text>

          
          <rect class="resistor-body" x="105" y="18" width="50" height="28" />
          <text class="label" x="130" y="32">R₁</text>

          
          <rect class="resistor-body" x="105" y="84" width="50" height="28" />
          <text class="label" x="130" y="98">R₂</text>

          
          <circle cx="15" cy="65" r="3.5" fill="#64748b" />
          <circle cx="245" cy="65" r="3.5" fill="#64748b" />
        </svg>
      </div>

      <div class="formula-badge">
        R<sub>eq</sub> =&nbsp;<span class="frac"><span class="frac-top">R₁ · R₂</span><span class="frac-bottom">R₁ + R₂</span></span>
      </div>
    </div>
  </div>

</body>
</html>

OGS.11.PS.PH.3

Aligned learning resources

Related diagrams