<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>Organism Energy Partition</title>
  <style>
    * {
      box-sizing: border-box;
      margin: 0;
      padding: 0;
      font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
    }
    body {
      background-color: #f8f9fa;
      color: #1e2945;
      width: 100%;
      min-height: 100%;
      display: flex;
      flex-direction: column;
      align-items: center;
      justify-content: center;
      padding: 8px;
      user-select: none;
    }

    .diagram-container {
      width: 100%;
      max-width: 560px;
      display: flex;
      flex-direction: column;
      gap: 8px;
    }

    /* Interactive energy controller */
    .controls {
      display: flex;
      align-items: center;
      justify-content: space-between;
      background: #ffffff;
      padding: 8px 12px;
      border-radius: 8px;
      border: 1px solid #e2e8f0;
      gap: 10px;
    }
    .controls label {
      font-size: 13px;
      font-weight: 700;
      color: #1e2945;
      white-space: nowrap;
    }
    .slider {
      flex: 1;
      accent-color: #0284c7;
      cursor: pointer;
      height: 6px;
    }
    .val-badge {
      font-size: 13px;
      font-weight: 800;
      color: #0284c7;
      min-width: 60px;
      text-align: right;
    }

    /* Main visual stage */
    .flow-svg {
      width: 100%;
      height: auto;
      display: block;
    }

    /* Formulas row */
    .formulas {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 8px;
    }
    .formula-card {
      background: #ffffff;
      border: 1px solid #e2e8f0;
      border-radius: 8px;
      padding: 6px 10px;
      text-align: center;
      font-size: 14px;
      font-weight: 600;
      display: flex;
      align-items: center;
      justify-content: center;
      gap: 5px;
    }
    .pill {
      display: inline-block;
      padding: 2px 6px;
      border-radius: 4px;
      font-weight: 700;
      font-size: 12px;
    }
    .pill-i { background: #e0f2fe; color: #0369a1; }
    .pill-f { background: #fef3c7; color: #92400e; }
    .pill-a { background: #e0e7ff; color: #3730a3; }
    .pill-r { background: #fee2e2; color: #991b1b; }
    .pill-p { background: #dcfce7; color: #166534; }

    /* Node styling */
    .node-group {
      cursor: default;
      transition: opacity 0.2s ease;
    }
    .node-group:hover {
      opacity: 0.92;
    }
    .node-rect {
      rx: 7;
      ry: 7;
      stroke-width: 1.5;
    }
    .node-title {
      font-size: 13.5px;
      font-weight: 700;
      fill: #1e2945;
    }
    .node-sub {
      font-size: 11.5px;
      font-weight: 500;
      fill: #4b5563;
    }
    .node-val {
      font-size: 12.5px;
      font-weight: 800;
    }
    .flow-line {
      fill: none;
      stroke-linecap: round;
      transition: stroke-width 0.2s ease;
    }

    @media (max-width: 400px) {
      .formula-card {
        font-size: 12px;
        padding: 5px 6px;
        gap: 3px;
      }
      .pill {
        padding: 1px 4px;
        font-size: 11px;
      }
    }
  </style>
</head>
<body>

<div class="diagram-container">
  
  <div class="controls">
    <label for="energyRange">Ingested Energy (I):</label>
    <input type="range" id="energyRange" class="slider" min="500" max="2000" step="100" value="1000">
    <span class="val-badge" id="rangeVal">1,000 J</span>
  </div>

  
  <svg class="flow-svg" viewBox="0 5 540 262">
    <defs>
      
      <linearGradient id="grad-I-F" x1="0%" y1="0%" x2="100%" y2="0%">
        <stop offset="0%" stop-color="#0284c7" />
        <stop offset="100%" stop-color="#d97706" />
      </linearGradient>
      <linearGradient id="grad-I-A" x1="0%" y1="0%" x2="100%" y2="0%">
        <stop offset="0%" stop-color="#0284c7" />
        <stop offset="100%" stop-color="#4f46e5" />
      </linearGradient>
      <linearGradient id="grad-A-R" x1="0%" y1="0%" x2="100%" y2="0%">
        <stop offset="0%" stop-color="#4f46e5" />
        <stop offset="100%" stop-color="#dc2626" />
      </linearGradient>
      <linearGradient id="grad-A-P" x1="0%" y1="0%" x2="100%" y2="0%">
        <stop offset="0%" stop-color="#4f46e5" />
        <stop offset="100%" stop-color="#16a34a" />
      </linearGradient>

      
      <marker id="arrow-f" viewBox="0 0 10 10" refX="6" refY="5" markerWidth="6" markerHeight="6" orient="auto">
        <path d="M 0 1 L 8 5 L 0 9 z" fill="#d97706" />
      </marker>
      <marker id="arrow-a" viewBox="0 0 10 10" refX="6" refY="5" markerWidth="6" markerHeight="6" orient="auto">
        <path d="M 0 1 L 8 5 L 0 9 z" fill="#4f46e5" />
      </marker>
      <marker id="arrow-r" viewBox="0 0 10 10" refX="6" refY="5" markerWidth="6" markerHeight="6" orient="auto">
        <path d="M 0 1 L 8 5 L 0 9 z" fill="#dc2626" />
      </marker>
      <marker id="arrow-p" viewBox="0 0 10 10" refX="6" refY="5" markerWidth="6" markerHeight="6" orient="auto">
        <path d="M 0 1 L 8 5 L 0 9 z" fill="#16a34a" />
      </marker>
    </defs>

    
    
    <path id="path-if" d="M 125 137 C 155 137, 155 47, 182 47" class="flow-line" stroke="url(#grad-I-F)" stroke-width="6" marker-end="url(#arrow-f)"/>
    
    <path id="path-ia" d="M 125 137 C 155 137, 155 197, 182 197" class="flow-line" stroke="url(#grad-I-A)" stroke-width="8" marker-end="url(#arrow-a)"/>
    
    <path id="path-ar" d="M 315 197 C 345 197, 345 137, 372 137" class="flow-line" stroke="url(#grad-A-R)" stroke-width="7" marker-end="url(#arrow-r)"/>
    
    <path id="path-ap" d="M 315 197 C 345 197, 345 229, 372 229" class="flow-line" stroke="url(#grad-A-P)" stroke-width="3" marker-end="url(#arrow-p)"/>

    
    <g class="node-group" transform="translate(10, 105)">
      <rect class="node-rect" width="115" height="65" fill="#e0f2fe" stroke="#0284c7" />
      <text x="57.5" y="22" text-anchor="middle" class="node-title">Ingested (I)</text>
      <text x="57.5" y="39" text-anchor="middle" class="node-sub">Food Eaten</text>
      <text id="txt-i" x="57.5" y="55" text-anchor="middle" class="node-val" fill="#0369a1">1,000 J</text>
    </g>

    
    <g class="node-group" transform="translate(185, 15)">
      <rect class="node-rect" width="130" height="65" fill="#fef3c7" stroke="#d97706" />
      <text x="65" y="22" text-anchor="middle" class="node-title">Egested (F)</text>
      <text x="65" y="39" text-anchor="middle" class="node-sub">Feces / Waste</text>
      <text id="txt-f" x="65" y="55" text-anchor="middle" class="node-val" fill="#92400e">500 J (50%)</text>
    </g>

    
    <g class="node-group" transform="translate(185, 165)">
      <rect class="node-rect" width="130" height="65" fill="#e0e7ff" stroke="#4f46e5" />
      <text x="65" y="22" text-anchor="middle" class="node-title">Assimilated (A)</text>
      <text x="65" y="39" text-anchor="middle" class="node-sub">Absorbed</text>
      <text id="txt-a" x="65" y="55" text-anchor="middle" class="node-val" fill="#3730a3">500 J (50%)</text>
    </g>

    
    <g class="node-group" transform="translate(375, 105)">
      <rect class="node-rect" width="155" height="65" fill="#fee2e2" stroke="#dc2626" />
      <text x="77.5" y="22" text-anchor="middle" class="node-title">Respiration (R)</text>
      <text x="77.5" y="39" text-anchor="middle" class="node-sub">Heat Loss / Work</text>
      <text id="txt-r" x="77.5" y="55" text-anchor="middle" class="node-val" fill="#991b1b">400 J (40%)</text>
    </g>

    
    <g class="node-group" transform="translate(375, 197)">
      <rect class="node-rect" width="155" height="65" fill="#dcfce7" stroke="#16a34a" />
      <text x="77.5" y="22" text-anchor="middle" class="node-title">Production (P<tspan font-size="10" dy="2.5">n</tspan><tspan dy="-2.5">)</tspan></text>
      <text x="77.5" y="39" text-anchor="middle" class="node-sub">Biomass / Growth</text>
      <text id="txt-p" x="77.5" y="55" text-anchor="middle" class="node-val" fill="#166534">100 J (10%)</text>
    </g>
  </svg>

  
  <div class="formulas">
    <div class="formula-card">
      <span class="pill pill-a">A</span> = <span class="pill pill-i">I</span> − <span class="pill pill-f">F</span>
    </div>
    <div class="formula-card">
      <span class="pill pill-p">P<sub>n</sub></span> = <span class="pill pill-a">A</span> − <span class="pill pill-r">R</span>
    </div>
  </div>
</div>

<script>
  const slider = document.getElementById('energyRange');
  const rangeVal = document.getElementById('rangeVal');
  const txtI = document.getElementById('txt-i');
  const txtF = document.getElementById('txt-f');
  const txtA = document.getElementById('txt-a');
  const txtR = document.getElementById('txt-r');
  const txtP = document.getElementById('txt-p');

  const pathIF = document.getElementById('path-if');
  const pathIA = document.getElementById('path-ia');
  const pathAR = document.getElementById('path-ar');
  const pathAP = document.getElementById('path-ap');

  function updateValues() {
    const val = parseInt(slider.value, 10);
    const fVal = Math.round(val * 0.5);
    const aVal = val - fVal;
    const rVal = Math.round(aVal * 0.8);
    const pVal = aVal - rVal;

    rangeVal.textContent = val.toLocaleString() + ' J';
    txtI.textContent = val.toLocaleString() + ' J';
    txtF.textContent = `${fVal.toLocaleString()} J (50%)`;
    txtA.textContent = `${aVal.toLocaleString()} J (50%)`;
    txtR.textContent = `${rVal.toLocaleString()} J (40%)`;
    txtP.textContent = `${pVal.toLocaleString()} J (10%)`;

    // Dynamically scale flow line widths to reflect energy magnitude
    pathIF.setAttribute('stroke-width', Math.max(3, (fVal / val) * 12));
    pathIA.setAttribute('stroke-width', Math.max(3, (aVal / val) * 12));
    pathAR.setAttribute('stroke-width', Math.max(2, (rVal / val) * 12));
    pathAP.setAttribute('stroke-width', Math.max(2, (pVal / val) * 12));
  }

  slider.addEventListener('input', updateValues);
  updateValues();
</script>

</body>
</html>

Thermodynamic Efficiency and Ecological Pyramids

<!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; 
      font-family: system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif; 
    }
    
    body {
      background: transparent;
      color: #1e2945;
      padding: 8px 6px;
      display: flex;
      flex-direction: column;
      align-items: center;
      min-height: 100%;
      overflow-x: hidden;
    }

    /* Tab Controls */
    .tab-bar {
      display: flex;
      gap: 8px;
      width: 100%;
      max-width: 480px;
      margin-bottom: 12px;
    }
    
    .tab-btn {
      flex: 1;
      padding: 8px 4px;
      border: 1.5px solid #cbd5e1;
      background: #f8fafc;
      color: #1e2945;
      font-size: 12.5px;
      font-weight: 700;
      border-radius: 8px;
      cursor: pointer;
      text-align: center;
      transition: background-color 0.35s ease, color 0.35s ease, border-color 0.35s ease, box-shadow 0.35s ease;
    }
    
    .tab-btn:hover {
      background: #f1f5f9;
      border-color: #94a3b8;
    }

    .tab-btn.active {
      background: #22b7ff;
      border-color: #0284c7;
      color: #ffffff;
      box-shadow: 0 2px 5px rgba(2, 132, 199, 0.3);
    }

    /* Panels Container */
    .content-area {
      width: 100%;
      max-width: 480px;
      position: relative;
    }
    
    .panel {
      display: none;
      width: 100%;
      animation: fadeIn 0.35s cubic-bezier(0.16, 1, 0.3, 1);
    }
    
    .panel.active {
      display: block;
    }

    @keyframes fadeIn {
      from { opacity: 0; transform: translateY(4px); }
      to { opacity: 1; transform: translateY(0); }
    }

    /* Comparison Grid for Biomass / Numbers */
    .grid-2 {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 8px;
    }

    /* Column Container without harsh card borders */
    .section-box {
      background: #ffffff;
      border-radius: 8px;
      padding: 10px 8px;
      display: flex;
      flex-direction: column;
      align-items: center;
      justify-content: space-between;
      min-height: 270px;
    }

    .sub-title {
      font-size: 12px;
      font-weight: 800;
      color: #1e2945;
      text-transform: uppercase;
      letter-spacing: 0.4px;
      margin-bottom: 10px;
      text-align: center;
      line-height: 1.2;
    }

    /* Tier Bars */
    .tier-stack {
      width: 100%;
      display: flex;
      flex-direction: column;
      align-items: center;
      justify-content: center;
      gap: 6px;
      flex-grow: 1;
    }
    
    .tier {
      display: flex;
      align-items: center;
      justify-content: space-between;
      height: 34px;
      padding: 0 8px;
      border-radius: 6px;
      font-size: 11.5px;
      font-weight: 700;
      color: #0f172a;
      box-shadow: 0 1px 3px rgba(0, 0, 0, 0.08);
      white-space: nowrap;
      transition: width 0.35s ease, background-color 0.35s ease;
    }

    /* Colors by Trophic Level */
    .t-apex { 
      background: #fed7aa; 
      border: 1.5px solid #ea580c; 
    }
    .t-carn { 
      background: #fef08a; 
      border: 1.5px solid #ca8a04; 
    }
    .t-herb { 
      background: #bae6fd; 
      border: 1.5px solid #0284c7; 
    }
    .t-prod { 
      background: #bbf7d0; 
      border: 1.5px solid #16a34a; 
    }

    .tier-name {
      display: flex;
      align-items: center;
      gap: 4px;
      flex-shrink: 1;
      overflow: hidden;
      text-overflow: ellipsis;
    }
    
    .tier-val {
      font-weight: 800;
      margin-left: 6px;
      flex-shrink: 0;
    }

    /* Informational Badges */
    .badge {
      font-size: 10.5px;
      font-weight: 700;
      padding: 4px 8px;
      border-radius: 10px;
      margin-top: 10px;
      text-align: center;
      line-height: 1.3;
    }
    
    .badge-blue {
      color: #0369a1;
      background: #e0f2fe;
      border: 1px solid #7dd3fc;
    }
    
    .badge-orange {
      color: #9a3412;
      background: #ffedd5;
      border: 1px solid #fdba74;
    }

    .badge-amber {
      color: #854d0e;
      background: #fef3c7;
      border: 1px solid #fde047;
    }

    @media (max-width: 400px) {
      body {
        padding: 6px 4px;
      }
      .tab-btn {
        font-size: 11px;
        padding: 7px 2px;
      }
      .tier {
        height: 32px;
        padding: 0 6px;
        font-size: 10.5px;
      }
      .tier-val {
        margin-left: 4px;
      }
      .sub-title {
        font-size: 11px;
        margin-bottom: 8px;
      }
      .badge {
        font-size: 9.5px;
        padding: 3px 6px;
      }
    }

    @media (max-width: 340px) {
      .grid-2 {
        grid-template-columns: 1fr;
      }
      .section-box {
        min-height: auto;
        padding: 8px 6px;
      }
    }
  </style>
</head>
<body>

  <div class="tab-bar" role="tablist">
    <button class="tab-btn active" role="tab" aria-selected="true" onclick="showTab(0)">⚡ Energy</button>
    <button class="tab-btn" role="tab" aria-selected="false" onclick="showTab(1)">⚖️ Biomass</button>
    <button class="tab-btn" role="tab" aria-selected="false" onclick="showTab(2)">🔢 Numbers</button>
  </div>

  <div class="content-area">
    
    <div class="panel active" id="tab-0" role="tabpanel">
      <div class="section-box">
        <div class="sub-title">Pyramid of Energy (Always Upright)</div>
        <div class="tier-stack">
          <div class="tier t-apex" style="width: 32%; min-width: 95px;">
            <span class="tier-name">🦅 Apex</span>
            <span class="tier-val">10 J</span>
          </div>
          <div class="tier t-carn" style="width: 54%; min-width: 140px;">
            <span class="tier-name">🐍 Carnivore</span>
            <span class="tier-val">100 J</span>
          </div>
          <div class="tier t-herb" style="width: 76%; min-width: 180px;">
            <span class="tier-name">🦗 Herbivore</span>
            <span class="tier-val">1,000 J</span>
          </div>
          <div class="tier t-prod" style="width: 98%; min-width: 215px;">
            <span class="tier-name">🌱 Producer</span>
            <span class="tier-val">10,000 J</span>
          </div>
        </div>
        <div class="badge badge-blue">90% Energy Lost per Step as Heat / Metabolism</div>
      </div>
    </div>

    
    <div class="panel" id="tab-1" role="tabpanel">
      <div class="grid-2">
        <div class="section-box">
          <div class="sub-title">Land (Upright)</div>
          <div class="tier-stack">
            <div class="tier t-carn" style="width: 36%; min-width: 70px;">
              <span class="tier-name">🦊 Fox</span>
              <span class="tier-val">0.1</span>
            </div>
            <div class="tier t-herb" style="width: 62%; min-width: 85px;">
              <span class="tier-name">🐇 Rabbit</span>
              <span class="tier-val">10 g</span>
            </div>
            <div class="tier t-prod" style="width: 98%;">
              <span class="tier-name">🌾 Grass</span>
              <span class="tier-val">800 g/m²</span>
            </div>
          </div>
          <div class="badge badge-blue">Standard Upright</div>
        </div>

        <div class="section-box">
          <div class="sub-title">Ocean (Inverted)</div>
          <div class="tier-stack">
            <div class="tier t-herb" style="width: 98%;">
              <span class="tier-name">🦐 Zooplankton</span>
              <span class="tier-val">21 g/m²</span>
            </div>
            <div class="tier t-prod" style="width: 48%; min-width: 92px;">
              <span class="tier-name">🦠 Phytopl.</span>
              <span class="tier-val">4 g/m²</span>
            </div>
          </div>
          <div class="badge badge-orange">Inverted Base (Rapid Turnover)</div>
        </div>
      </div>
    </div>

    
    <div class="panel" id="tab-2" role="tabpanel">
      <div class="grid-2">
        <div class="section-box">
          <div class="sub-title">Grassland</div>
          <div class="tier-stack">
            <div class="tier t-apex" style="width: 30%; min-width: 60px;">
              <span class="tier-name">🦅 Hawk</span>
              <span class="tier-val">1</span>
            </div>
            <div class="tier t-herb" style="width: 60%; min-width: 85px;">
              <span class="tier-name">🐭 Mice</span>
              <span class="tier-val">1,000</span>
            </div>
            <div class="tier t-prod" style="width: 98%;">
              <span class="tier-name">🌾 Grass</span>
              <span class="tier-val">100,000</span>
            </div>
          </div>
          <div class="badge badge-blue">Standard Upright</div>
        </div>

        <div class="section-box">
          <div class="sub-title">Oak Tree</div>
          <div class="tier-stack">
            <div class="tier t-carn" style="width: 35%; min-width: 65px;">
              <span class="tier-name">🐦 Birds</span>
              <span class="tier-val">5</span>
            </div>
            <div class="tier t-herb" style="width: 98%;">
              <span class="tier-name">🐛 Insects</span>
              <span class="tier-val">100,000</span>
            </div>
            <div class="tier t-prod" style="width: 30%; min-width: 60px;">
              <span class="tier-name">🌳 Oak</span>
              <span class="tier-val">1</span>
            </div>
          </div>
          <div class="badge badge-amber">Spindle Shape (Single Host)</div>
        </div>
      </div>
    </div>
  </div>

  <script>
    function showTab(idx) {
      document.querySelectorAll('.tab-btn').forEach((btn, i) => {
        const isActive = i === idx;
        btn.classList.toggle('active', isActive);
        btn.setAttribute('aria-selected', isActive ? 'true' : 'false');
      });
      document.querySelectorAll('.panel').forEach((panel, i) => {
        panel.classList.toggle('active', i === idx);
      });
    }
  </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">
  <title>Thermodynamic Energy Flow</title>
  <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: 10px;
      display: flex;
      flex-direction: column;
      align-items: center;
      justify-content: center;
      min-height: 100vh;
      gap: 10px;
    }

    .main-wrapper {
      width: 100%;
      max-width: 560px;
      display: flex;
      flex-direction: column;
      gap: 10px;
    }

    .header-hint {
      text-align: center;
      font-size: 12px;
      font-weight: 600;
      color: #64748b;
    }

    /* Trophic Chain Grid - Acts as Primary Navigation */
    .trophic-chain {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 6px;
      width: 100%;
    }
    @media (max-width: 380px) {
      .trophic-chain {
        grid-template-columns: repeat(2, 1fr);
      }
    }

    .level-card {
      background: #ffffff;
      border: 1px solid #e6e6e6;
      border-radius: 8px;
      padding: 8px 4px;
      text-align: center;
      cursor: pointer;
      user-select: none;
      transition: border-color 0.2s, box-shadow 0.2s, background-color 0.2s;
      display: flex;
      flex-direction: column;
      align-items: center;
      justify-content: space-between;
      min-height: 94px;
    }
    .level-card:hover {
      border-color: #22b7ff;
      background: #f8fcff;
    }
    .level-card.active {
      border-color: #0284c7;
      background: #f0f9ff;
      box-shadow: 0 0 0 2px #0284c7;
    }
    .level-card:focus-visible {
      outline: 2px solid #0284c7;
      outline-offset: 2px;
    }
    .level-card .emoji {
      font-size: 20px;
      line-height: 1;
      margin-bottom: 2px;
    }
    .level-card .name {
      font-size: 11px;
      font-weight: 700;
      color: #1e2945;
      line-height: 1.2;
    }
    .level-card .energy-bar {
      width: 88%;
      height: 5px;
      background: #e2e8f0;
      border-radius: 3px;
      margin: 4px 0;
      overflow: hidden;
    }
    .level-card .energy-fill {
      height: 100%;
      background: #0284c7;
      border-radius: 3px;
    }
    .level-card .val {
      font-size: 11px;
      font-weight: 700;
      color: #0284c7;
      font-variant-numeric: tabular-nums;
    }

    /* Dynamic Detailed Flow View */
    .flow-display {
      background: #ffffff;
      border: 1px solid #e6e6e6;
      border-radius: 10px;
      padding: 8px 6px;
      position: relative;
      width: 100%;
      box-shadow: 0 1px 3px rgba(0,0,0,0.04);
    }

    .svg-flow {
      width: 100%;
      height: auto;
      display: block;
    }

    .flow-text {
      font-size: 11px;
      font-weight: 700;
      fill: #1e2945;
    }
    .heat-title {
      font-size: 10px;
      font-weight: 700;
      fill: #c2410c;
    }
    .heat-sub {
      font-size: 8.5px;
      font-weight: 600;
      fill: #c2410c;
    }
    .detritus-text {
      font-size: 9.5px;
      font-weight: 600;
      fill: #6d28d9;
    }
  </style>
</head>
<body>

  <div class="main-wrapper">
    <div class="header-hint">Select a trophic level to observe energy fate &amp; 2nd Law entropy:</div>

    
    <div class="trophic-chain" role="tablist" aria-label="Trophic Levels">
      <button class="level-card active" onclick="selectLevel(0)" id="card0" role="tab" aria-selected="true" tabindex="0">
        <span class="emoji">🌱</span>
        <span class="name">Producers</span>
        <div class="energy-bar"><div class="energy-fill" style="width: 100%;"></div></div>
        <span class="val">10,000 J</span>
      </button>
      <button class="level-card" onclick="selectLevel(1)" id="card1" role="tab" aria-selected="false" tabindex="0">
        <span class="emoji">🐛</span>
        <span class="name">1° Consumers</span>
        <div class="energy-bar"><div class="energy-fill" style="width: 25%;"></div></div>
        <span class="val">1,000 J</span>
      </button>
      <button class="level-card" onclick="selectLevel(2)" id="card2" role="tab" aria-selected="false" tabindex="0">
        <span class="emoji">🐦</span>
        <span class="name">2° Consumers</span>
        <div class="energy-bar"><div class="energy-fill" style="width: 12%;"></div></div>
        <span class="val">100 J</span>
      </button>
      <button class="level-card" onclick="selectLevel(3)" id="card3" role="tab" aria-selected="false" tabindex="0">
        <span class="emoji">🦅</span>
        <span class="name">3° Consumers</span>
        <div class="energy-bar"><div class="energy-fill" style="width: 4%;"></div></div>
        <span class="val">10 J</span>
      </button>
    </div>

    
    <div class="flow-display" role="tabpanel" aria-labelledby="card0">
      <svg class="svg-flow" viewBox="0 0 360 145" aria-label="Thermodynamic Energy Flow Diagram">
        <defs>
          <marker id="arrowBlue" markerWidth="6" markerHeight="6" refX="4" refY="3" orient="auto">
            <path d="M0,0 L6,3 L0,6 Z" fill="#0284c7" />
          </marker>
          <marker id="arrowOrange" markerWidth="6" markerHeight="6" refX="4" refY="3" orient="auto">
            <path d="M0,0 L6,3 L0,6 Z" fill="#c2410c" />
          </marker>
          <marker id="arrowPurple" markerWidth="6" markerHeight="6" refX="4" refY="3" orient="auto">
            <path d="M0,0 L6,3 L0,6 Z" fill="#7c3aed" />
          </marker>
        </defs>

        
        <path d="M 8 72 L 98 72" stroke="#0284c7" stroke-width="5" fill="none" marker-end="url(#arrowBlue)" stroke-linecap="round"/>
        <text x="10" y="58" class="flow-text" id="inText">10,000 J IN</text>
        <text x="10" y="90" font-size="8.5" font-weight="600" fill="#64748b" id="inLabel">Gross Intake</text>

        
        <rect x="108" y="46" width="112" height="52" rx="8" fill="#f8fafc" stroke="#0284c7" stroke-width="2"/>
        <text x="164" y="68" text-anchor="middle" font-size="12" font-weight="700" fill="#1e2945" id="centerNodeName">Producers</text>
        <text x="164" y="86" text-anchor="middle" font-size="10.5" font-weight="700" fill="#0284c7" id="centerNodeVal">10,000 J</text>

        
        <path d="M 164 44 C 156 32, 172 24, 164 12" stroke="#c2410c" stroke-width="4.5" fill="none" marker-end="url(#arrowOrange)" stroke-linecap="round"/>
        <text x="176" y="17" class="heat-title">🔥 Metabolic Heat Loss</text>
        <text x="176" y="30" class="heat-sub" id="heatVal">9,000 J (Entropy - 2nd Law)</text>

        
        <path d="M 164 100 L 164 126" stroke="#7c3aed" stroke-width="2.5" fill="none" marker-end="url(#arrowPurple)" stroke-linecap="round" stroke-dasharray="3 3"/>
        <text x="176" y="122" class="detritus-text">🍄 Detritivores / Waste</text>
        <text x="176" y="134" font-size="8" font-weight="600" fill="#7c3aed" id="detritusVal">~10% Unassimilated</text>

        
        <path d="M 222 72 L 282 72" stroke="#0284c7" stroke-width="3" fill="none" marker-end="url(#arrowBlue)" stroke-linecap="round"/>
        <text x="232" y="60" font-size="10" font-weight="700" fill="#0284c7" id="nextText">➡️ 1,000 J (10%)</text>
        <text x="232" y="88" font-size="9" font-weight="600" fill="#64748b" id="nextLabel">to Primary</text>
      </svg>
    </div>
  </div>

  <script>
    const levels = [
      { name: "Producers", in: "10,000 J IN", inLbl: "Solar Energy", val: "10,000 J", heat: "9,000 J (Entropy - 2nd Law)", detritus: "~10% Plant Litter", next: "➡️ 1,000 J (10%)", target: "to 1° Consumers" },
      { name: "1° Consumers", in: "1,000 J IN", inLbl: "Herbivore Intake", val: "1,000 J", heat: "900 J (Entropy - 2nd Law)", detritus: "~10% Feces / Death", next: "➡️ 100 J (10%)", target: "to 2° Consumers" },
      { name: "2° Consumers", in: "100 J IN", inLbl: "Carnivore Intake", val: "100 J", heat: "90 J (Entropy - 2nd Law)", detritus: "~10% Carcasses", next: "➡️ 10 J (10%)", target: "to 3° Consumers" },
      { name: "3° Consumers", in: "10 J IN", inLbl: "Apex Intake", val: "10 J", heat: "9 J (Entropy - 2nd Law)", detritus: "~1 J to Decomposers", next: "➡️ 1 J (10%)", target: "Apex Biomass" }
    ];

    function selectLevel(idx) {
      // Update Cards
      for (let i = 0; i < 4; i++) {
        const card = document.getElementById('card' + i);
        if (card) {
          const isActive = (i === idx);
          card.classList.toggle('active', isActive);
          card.setAttribute('aria-selected', isActive ? 'true' : 'false');
        }
      }

      // Update SVG Content
      const data = levels[idx];
      document.getElementById('inText').textContent = data.in;
      document.getElementById('inLabel').textContent = data.inLbl;
      document.getElementById('centerNodeName').textContent = data.name;
      document.getElementById('centerNodeVal').textContent = data.val;
      document.getElementById('heatVal').textContent = data.heat;
      document.getElementById('detritusVal').textContent = data.detritus;
      document.getElementById('nextText').textContent = data.next;
      document.getElementById('nextLabel').textContent = data.target;
    }

    // Keyboard support for arrow navigation
    document.querySelectorAll('.level-card').forEach((card, idx) => {
      card.addEventListener('keydown', (e) => {
        if (e.key === 'ArrowRight' || e.key === 'ArrowDown') {
          e.preventDefault();
          const next = (idx + 1) % 4;
          document.getElementById('card' + next).focus();
          selectLevel(next);
        } else if (e.key === 'ArrowLeft' || e.key === 'ArrowUp') {
          e.preventDefault();
          const prev = (idx + 3) % 4;
          document.getElementById('card' + prev).focus();
          selectLevel(prev);
        }
      });
    });
  </script>
</body>
</html>

Top-Down versus Bottom-Up Control and Trophic Cascades

Global Carbon Cycle Fluxes and Deep Geosphere Sinks

Nitrogen Cycle Biochemical Pathways and Microbial Drivers

Phosphorus Cycle: Weathering, Sedimentation, and Eutrophication

Global Hydrologic Fluxes, Residence Times, and Energy Transfer

science

Trophic Energetics, Cascades, and Biogeochemical Cycles

Pengenalan Biomolekul dan Fungsinya

Karbohidrat: Struktur dan Fungsi

Lipid: Struktur dan Fungsi

Protein: Struktur dan Fungsi

Enzim: Katalis Biologis dan Mekanismenya

Faktor yang Mempengaruhi Aktivitas Enzim

Diferensiasi Sel menjadi Jaringan dan Organ

Biomolekul, Enzim, dan Diferensiasi Sel

Modeling Energy Pyramids and the Ten Percent Law

Food Web Dynamics and Trophic Cascade Disruption

Biomass Accumulation and Decomposer Functions

Assessing Disruption Impacts on Primary Productivity

Bioaccumulation and Biomagnification Across Trophic Levels

Analyzing Quantitative Data from Trophic Models

Communicating Ecosystem Energy Flow Models Collaboratively

Matter Cycling and Energy Flow in Ecosystems

Factors Affecting Reaction Rates: Temperature

Factors Affecting Reaction Rates: Concentration

Factors Affecting Reaction Rates: Surface Area

Factors Affecting Reaction Rates: Catalysts

Investigating Reaction Rate with Changing Temperature

Interpreting Reaction Rate Graphs

Factors That Affect How Fast Equilibrium Is Reached

Chemical Reaction Products and Global Climate Change

Reaction Rates and Equilibrium

Reservoirs and Processes in the Carbon Cycle

Nitrogen Fixation, Nitrification, and Denitrification

Consequences of Nitrogen Over-enrichment and Eutrophication

Human Disruptions to Biogeochemical Cycles: Synthetic Fertilizers and Fossil Fuels

OGS.11.ESS.2

Aligned learning resources

Related diagrams