<!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: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
      background: transparent;
      color: #1e293b;
      padding: 12px;
      display: flex;
      flex-direction: column;
      gap: 12px;
      user-select: none;
      -webkit-user-select: none;
    }

    /* 3 Formula Cards */
    .rules-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 8px;
    }
    .rule-card {
      padding: 8px 6px;
      border-radius: 10px;
      text-align: center;
      display: flex;
      flex-direction: column;
      gap: 4px;
      transition: box-shadow 0.2s ease;
    }
    .rule-card.p-card { background: #ecfdf5; border: 1px solid #a7f3d0; color: #065f46; }
    .rule-card.n-card { background: #fffbeb; border: 1px solid #fde68a; color: #92400e; }
    .rule-card.e-card { background: #f5f3ff; border: 1px solid #ddd6fe; color: #5b21b6; }

    .rule-title {
      font-size: 11px;
      font-weight: 700;
      text-transform: uppercase;
      letter-spacing: 0.5px;
      opacity: 0.85;
    }
    .rule-formula {
      font-size: 14px;
      font-weight: 800;
      font-family: "SF Mono", "Segoe UI Mono", "Courier New", monospace;
    }

    /* Example Section */
    .example-panel {
      background: #f8fafc;
      border: 1px solid #e2e8f0;
      border-radius: 12px;
      padding: 12px;
      display: flex;
      flex-direction: column;
      gap: 10px;
    }

    /* Isotope Switcher Tabs */
    .tabs-row {
      display: flex;
      gap: 6px;
      justify-content: center;
    }
    .tab-btn {
      background: #ffffff;
      border: 1px solid #cbd5e1;
      border-radius: 8px;
      padding: 4px 10px;
      font-size: 13px;
      font-weight: 700;
      color: #64748b;
      cursor: pointer;
      font-family: inherit;
    }
    .tab-btn.active {
      background: #1e293b;
      border-color: #1e293b;
      color: #ffffff;
    }

    /* Worked Content Layout */
    .calc-layout {
      display: flex;
      align-items: center;
      gap: 14px;
    }

    /* Nuclide Visual Box */
    .nuclide-badge {
      background: #ffffff;
      border: 1.5px solid #cbd5e1;
      border-radius: 10px;
      padding: 8px 12px;
      display: inline-flex;
      align-items: center;
      justify-content: center;
      min-width: 80px;
      box-shadow: 0 1px 3px rgba(0,0,0,0.04);
    }
    .nuclide-box {
      display: inline-grid;
      grid-template-columns: auto auto auto;
      grid-template-rows: auto auto;
      align-items: center;
      font-family: "SF Mono", "Segoe UI Mono", monospace;
      line-height: 1;
    }
    .val-a {
      grid-column: 1; grid-row: 1;
      font-size: 13px; font-weight: 800;
      color: #d97706; text-align: right;
      padding-right: 2px;
    }
    .val-z {
      grid-column: 1; grid-row: 2;
      font-size: 13px; font-weight: 800;
      color: #059669; text-align: right;
      padding-right: 2px;
    }
    .val-sym {
      grid-column: 2; grid-row: 1 / span 2;
      font-size: 30px; font-weight: 900;
      color: #0f172a; padding: 0 2px;
    }
    .val-chg {
      grid-column: 3; grid-row: 1;
      font-size: 13px; font-weight: 800;
      color: #7c3aed; text-align: left;
      min-height: 13px;
    }

    /* Steps Column */
    .steps-col {
      flex: 1;
      display: flex;
      flex-direction: column;
      gap: 6px;
    }
    .calc-row {
      display: flex;
      align-items: center;
      justify-content: space-between;
      background: #ffffff;
      border: 1px solid #e2e8f0;
      border-radius: 6px;
      padding: 5px 8px;
      font-size: 13px;
      font-weight: 600;
      font-family: "SF Mono", "Segoe UI Mono", monospace;
    }
    .calc-row.p-row { border-left: 3px solid #10b981; }
    .calc-row.n-row { border-left: 3px solid #f59e0b; }
    .calc-row.e-row { border-left: 3px solid #8b5cf6; }

    .calc-label {
      font-size: 12px;
      font-weight: 700;
      font-family: -apple-system, BlinkMacSystemFont, sans-serif;
    }
    .p-row .calc-label { color: #059669; }
    .n-row .calc-label { color: #d97706; }
    .e-row .calc-label { color: #7c3aed; }

    .calc-math { color: #334155; }
    .calc-res { font-weight: 800; color: #0f172a; }

    @media (max-width: 340px) {
      .rules-grid { gap: 4px; }
      .rule-formula { font-size: 12px; }
      .calc-layout { flex-direction: column; gap: 8px; }
      .nuclide-badge { width: 100%; }
    }
  </style>
</head>
<body>

  
  <div class="rules-grid">
    <div class="rule-card p-card">
      <span class="rule-title">Protons</span>
      <span class="rule-formula">p = Z</span>
    </div>
    <div class="rule-card n-card">
      <span class="rule-title">Neutrons</span>
      <span class="rule-formula">n = A − Z</span>
    </div>
    <div class="rule-card e-card">
      <span class="rule-title">Electrons</span>
      <span class="rule-formula">e = p − (charge)</span>
    </div>
  </div>

  
  <div class="example-panel">
    <div class="tabs-row">
      <button class="tab-btn active" onclick="showIsotope(0)">¹⁴₆C</button>
      <button class="tab-btn" onclick="showIsotope(1)">²³₁₁Na⁺</button>
      <button class="tab-btn" onclick="showIsotope(2)">¹⁶₈O²⁻</button>
    </div>

    <div class="calc-layout">
      
      <div class="nuclide-badge">
        <div class="nuclide-box">
          <span class="val-a" id="symA">14</span>
          <span class="val-z" id="symZ">6</span>
          <span class="val-sym" id="symEl">C</span>
          <span class="val-chg" id="symChg"></span>
        </div>
      </div>

      
      <div class="steps-col">
        <div class="calc-row p-row">
          <span class="calc-label">p</span>
          <span class="calc-math" id="mathP">p = 6</span>
          <span class="calc-res" id="resP">6</span>
        </div>
        <div class="calc-row n-row">
          <span class="calc-label">n</span>
          <span class="calc-math" id="mathN">14 − 6</span>
          <span class="calc-res" id="resN">8</span>
        </div>
        <div class="calc-row e-row">
          <span class="calc-label">e</span>
          <span class="calc-math" id="mathE">6 − (0)</span>
          <span class="calc-res" id="resE">6</span>
        </div>
      </div>
    </div>
  </div>

  <script>
    const data = [
      { sym: 'C', a: 14, z: 6, chgStr: '', chgVal: 0 },
      { sym: 'Na', a: 23, z: 11, chgStr: '+', chgVal: 1 },
      { sym: 'O', a: 16, z: 8, chgStr: '2−', chgVal: -2 }
    ];

    function showIsotope(idx) {
      const item = data[idx];
      const p = item.z;
      const n = item.a - item.z;
      const e = p - item.chgVal;

      document.querySelectorAll('.tab-btn').forEach((b, i) => {
        b.classList.toggle('active', i === idx);
      });

      document.getElementById('symA').textContent = item.a;
      document.getElementById('symZ').textContent = item.z;
      document.getElementById('symEl').textContent = item.sym;
      document.getElementById('symChg').textContent = item.chgStr;

      document.getElementById('mathP').textContent = `p = ${p}`;
      document.getElementById('resP').textContent = p;

      document.getElementById('mathN').textContent = `${item.a} − ${item.z}`;
      document.getElementById('resN').textContent = n;

      const signStr = item.chgVal > 0 ? `+${item.chgVal}` : `${item.chgVal}`;
      document.getElementById('mathE').textContent = `${p} − (${item.chgVal === 0 ? '0' : signStr})`;
      document.getElementById('resE').textContent = e;
    }
  </script>
</body>
</html>

Nuclide Notation and Isotopic Composition

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

    .diagram-grid {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 12px;
      width: 100%;
      max-width: 380px;
    }

    .isotope-card {
      background: #ffffff;
      border: 1.5px solid #e2e8f0;
      border-radius: 12px;
      padding: 12px 10px;
      display: flex;
      flex-direction: column;
      align-items: center;
      box-shadow: 0 2px 6px rgba(0, 0, 0, 0.04);
    }

    .symbol-box {
      display: flex;
      align-items: center;
      justify-content: center;
      margin-bottom: 12px;
      font-weight: 700;
      line-height: 1;
    }

    .scripts {
      display: flex;
      flex-direction: column;
      font-size: 15px;
      text-align: right;
      margin-right: 2px;
      line-height: 1.1;
    }

    .mass-num {
      color: #d97706;
      font-weight: 800;
    }

    .atomic-num {
      color: #2563eb;
      font-weight: 800;
    }

    .element-sym {
      font-size: 34px;
      letter-spacing: -0.5px;
    }

    .particle-list {
      display: flex;
      flex-direction: column;
      gap: 6px;
      width: 100%;
    }

    .row {
      display: flex;
      justify-content: space-between;
      align-items: center;
      padding: 6px 8px;
      border-radius: 6px;
      font-size: 13px;
      font-weight: 600;
    }

    .same {
      background: #eff6ff;
      color: #1d4ed8;
      border: 1px solid #dbeafe;
    }

    .diff {
      background: #fff7ed;
      color: #c2410c;
      border: 1px solid #ffedd5;
    }

    .calc {
      font-size: 11px;
      font-weight: 500;
      opacity: 0.85;
    }

    .callout-pill {
      margin-top: 12px;
      background: #ea580c;
      color: #ffffff;
      padding: 6px 14px;
      border-radius: 20px;
      font-size: 13px;
      font-weight: 700;
      text-align: center;
      box-shadow: 0 2px 4px rgba(234, 88, 12, 0.2);
    }
  </style>
</head>
<body>

  <div class="diagram-grid">
    
    <div class="isotope-card">
      <div class="symbol-box">
        <div class="scripts">
          <span class="mass-num">35</span>
          <span class="atomic-num">17</span>
        </div>
        <span class="element-sym">Cl</span>
      </div>

      <div class="particle-list">
        <div class="row same">
          <span>17 Protons</span>
          <span>p⁺</span>
        </div>
        <div class="row diff">
          <span>18 Neutrons</span>
          <span class="calc">35−17</span>
        </div>
        <div class="row same">
          <span>17 Electrons</span>
          <span>e⁻</span>
        </div>
      </div>
    </div>

    
    <div class="isotope-card">
      <div class="symbol-box">
        <div class="scripts">
          <span class="mass-num">37</span>
          <span class="atomic-num">17</span>
        </div>
        <span class="element-sym">Cl</span>
      </div>

      <div class="particle-list">
        <div class="row same">
          <span>17 Protons</span>
          <span>p⁺</span>
        </div>
        <div class="row diff">
          <span>20 Neutrons</span>
          <span class="calc">37−17</span>
        </div>
        <div class="row same">
          <span>17 Electrons</span>
          <span>e⁻</span>
        </div>
      </div>
    </div>
  </div>

  <div class="callout-pill">
    Differs by 2 neutrons
  </div>

</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">
  <link rel="stylesheet" href="{{VENDOR_CDN}}/katex.min.css" />
  <script src="{{VENDOR_CDN}}/katex.min.js"></script>
  <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;
      padding: 12px;
      display: flex;
      justify-content: center;
      align-items: center;
      min-height: 100%;
    }
    .grid-container {
      width: 100%;
      max-width: 660px;
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 12px;
    }
    @media (max-width: 460px) {
      .grid-container {
        grid-template-columns: 1fr;
        gap: 10px;
      }
    }
    .ion-card {
      background: #ffffff;
      border: 1px solid #e2e8f0;
      border-radius: 10px;
      padding: 14px 12px;
      display: flex;
      flex-direction: column;
      gap: 10px;
      box-shadow: 0 1px 3px rgba(0,0,0,0.04);
    }
    .cation-card {
      border-top: 4px solid #ef4444;
    }
    .anion-card {
      border-top: 4px solid #10b981;
    }
    .card-header {
      text-align: center;
      display: flex;
      flex-direction: column;
      align-items: center;
      gap: 4px;
    }
    .symbol-display {
      font-size: 26px;
      line-height: 1.2;
      min-height: 38px;
    }
    .card-title {
      font-size: 14px;
      font-weight: 700;
      color: #0f172a;
    }
    .pill {
      font-size: 11px;
      font-weight: 700;
      padding: 2px 8px;
      border-radius: 9999px;
      text-transform: uppercase;
      letter-spacing: 0.3px;
    }
    .pill-red {
      background: #fee2e2;
      color: #b91c1c;
    }
    .pill-green {
      background: #dcfce7;
      color: #15803d;
    }
    .rows {
      display: flex;
      flex-direction: column;
      gap: 6px;
    }
    .particle-row {
      display: flex;
      align-items: center;
      justify-content: space-between;
      background: #f8fafc;
      border: 1px solid #edf2f7;
      border-radius: 6px;
      padding: 5px 8px;
      font-size: 12px;
    }
    .particle-row.highlight-calc {
      background: #fffbeb;
      border-color: #fde68a;
    }
    .particle-label {
      display: flex;
      align-items: center;
      gap: 6px;
      font-weight: 600;
      color: #334155;
    }
    .badge {
      display: inline-flex;
      align-items: center;
      justify-content: center;
      width: 22px;
      height: 22px;
      border-radius: 50%;
      font-weight: 700;
      font-size: 11px;
      color: #ffffff;
      flex-shrink: 0;
    }
    .badge-p { background: #2563eb; }
    .badge-n { background: #64748b; }
    .badge-e { background: #d97706; }
    .calc-math {
      font-family: ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, monospace;
      font-size: 12px;
      font-weight: 600;
      color: #1e2945;
    }
    .calc-math strong {
      font-size: 13px;
      color: #0f172a;
    }
    .balance-box {
      border-top: 1px dashed #cbd5e1;
      padding-top: 8px;
      display: flex;
      flex-direction: column;
      gap: 4px;
    }
    .balance-bar-wrap {
      display: flex;
      height: 10px;
      border-radius: 5px;
      overflow: hidden;
      background: #e2e8f0;
      width: 100%;
    }
    .bar-p { background: #3b82f6; }
    .bar-e { background: #f59e0b; }
    .balance-footer {
      display: flex;
      justify-content: space-between;
      align-items: center;
      font-size: 11px;
      font-weight: 700;
      color: #475569;
    }
    .net-charge {
      font-size: 12px;
      font-weight: 800;
      padding: 1px 6px;
      border-radius: 4px;
    }
    .net-pos {
      background: #fef2f2;
      color: #dc2626;
      border: 1px solid #fecaca;
    }
    .net-neg {
      background: #f0fdf4;
      color: #16a34a;
      border: 1px solid #bbf7d0;
    }
  </style>
</head>
<body>

  <div class="grid-container">
    
    <div class="ion-card cation-card">
      <div class="card-header">
        <div class="symbol-display" id="cation-sym"></div>
        <div class="card-title">Cation (Positive Ion)</div>
        <span class="pill pill-red">Lost 3 e⁻</span>
      </div>

      <div class="rows">
        <div class="particle-row">
          <div class="particle-label">
            <span class="badge badge-p">p⁺</span>
            <span>Protons (Z)</span>
          </div>
          <span class="calc-math">26</span>
        </div>

        <div class="particle-row">
          <div class="particle-label">
            <span class="badge badge-n">n⁰</span>
            <span>Neutrons (A−Z)</span>
          </div>
          <span class="calc-math">56 − 26 = <strong>30</strong></span>
        </div>

        <div class="particle-row highlight-calc">
          <div class="particle-label">
            <span class="badge badge-e">e⁻</span>
            <span>Electrons</span>
          </div>
          <span class="calc-math">26 − (+3) = <strong>23</strong></span>
        </div>
      </div>

      <div class="balance-box">
        <div class="balance-bar-wrap" title="26 Protons vs 23 Electrons">
          <div class="bar-p" style="width: 53.06%;"></div>
          <div class="bar-e" style="width: 46.94%;"></div>
        </div>
        <div class="balance-footer">
          <span>26 p⁺ &gt; 23 e⁻</span>
          <span class="net-charge net-pos">Net: +3</span>
        </div>
      </div>
    </div>

    
    <div class="ion-card anion-card">
      <div class="card-header">
        <div class="symbol-display" id="anion-sym"></div>
        <div class="card-title">Anion (Negative Ion)</div>
        <span class="pill pill-green">Gained 2 e⁻</span>
      </div>

      <div class="rows">
        <div class="particle-row">
          <div class="particle-label">
            <span class="badge badge-p">p⁺</span>
            <span>Protons (Z)</span>
          </div>
          <span class="calc-math">16</span>
        </div>

        <div class="particle-row">
          <div class="particle-label">
            <span class="badge badge-n">n⁰</span>
            <span>Neutrons (A−Z)</span>
          </div>
          <span class="calc-math">32 − 16 = <strong>16</strong></span>
        </div>

        <div class="particle-row highlight-calc">
          <div class="particle-label">
            <span class="badge badge-e">e⁻</span>
            <span>Electrons</span>
          </div>
          <span class="calc-math">16 − (−2) = <strong>18</strong></span>
        </div>
      </div>

      <div class="balance-box">
        <div class="balance-bar-wrap" title="16 Protons vs 18 Electrons">
          <div class="bar-p" style="width: 47.06%;"></div>
          <div class="bar-e" style="width: 52.94%;"></div>
        </div>
        <div class="balance-footer">
          <span>16 p⁺ &lt; 18 e⁻</span>
          <span class="net-charge net-neg">Net: −2</span>
        </div>
      </div>
    </div>
  </div>

  <script>
    function renderMath() {
      const cationEl = document.getElementById('cation-sym');
      const anionEl = document.getElementById('anion-sym');

      if (window.katex) {
        katex.render("^{56}_{26}\\text{Fe}^{3+}", cationEl, { throwOnError: false });
        katex.render("^{32}_{16}\\text{S}^{2-}", anionEl, { throwOnError: false });
      } else {
        cationEl.innerHTML = "<sup>56</sup><sub>26</sub>Fe<sup>3+</sup>";
        anionEl.innerHTML = "<sup>32</sup><sub>16</sub>S<sup>2-</sup>";
      }
    }
    document.addEventListener("DOMContentLoaded", renderMath);
    if (document.readyState === "complete" || document.readyState === "interactive") {
      renderMath();
    }
  </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="1:1">
  <script src="{{VENDOR_CDN}}/classace-diagram.js"></script>
  <style>
    * { box-sizing: border-box; margin: 0; padding: 0; }
    body {
      font-family: system-ui, -apple-system, sans-serif;
      background: #f8fafc;
      color: #1e2945;
      display: flex;
      flex-direction: column;
      align-items: center;
      justify-content: center;
      min-height: 100vh;
      padding: 12px;
      user-select: none;
    }
    .nuclide-board {
      width: 100%;
      max-width: 340px;
      display: flex;
      flex-direction: column;
      gap: 12px;
      align-items: center;
    }
    .grid-container {
      display: grid;
      grid-template-columns: 1fr 1.3fr 1fr;
      grid-template-rows: auto auto;
      gap: 10px 8px;
      width: 100%;
      align-items: center;
    }
    .badge-btn {
      background: #ffffff;
      border: 1.5px solid #e2e8f0;
      border-radius: 8px;
      padding: 6px 8px;
      cursor: pointer;
      text-align: center;
      transition: all 0.25s ease;
      display: flex;
      flex-direction: column;
      gap: 2px;
    }
    .badge-btn:hover {
      box-shadow: 0 2px 6px rgba(0,0,0,0.06);
    }
    .badge-btn .title {
      font-size: 11px;
      font-weight: 700;
      letter-spacing: 0.2px;
    }
    .badge-btn .formula {
      font-size: 10px;
      color: #64748b;
      font-weight: 600;
    }

    /* Color specific styling */
    .b-mass { border-color: #fde68a; }
    .b-mass .title { color: #d97706; }
    .b-mass.active { background: #fffbeb; border-color: #d97706; box-shadow: 0 0 0 2px rgba(217,119,6,0.25); }

    .b-charge { border-color: #ddd6fe; }
    .b-charge .title { color: #7c3aed; }
    .b-charge.active { background: #f5f3ff; border-color: #7c3aed; box-shadow: 0 0 0 2px rgba(124,58,237,0.25); }

    .b-atomic { border-color: #a7f3d0; }
    .b-atomic .title { color: #059669; }
    .b-atomic.active { background: #ecfdf5; border-color: #059669; box-shadow: 0 0 0 2px rgba(5,150,105,0.25); }

    .b-symbol { border-color: #cbd5e1; }
    .b-symbol .title { color: #1e2945; }
    .b-symbol.active { background: #f1f5f9; border-color: #1e2945; box-shadow: 0 0 0 2px rgba(30,41,69,0.25); }

    /* Center Element Tile */
    .symbol-tile {
      grid-column: 2;
      grid-row: 1 / span 2;
      background: #ffffff;
      border: 2px solid #cbd5e1;
      border-radius: 12px;
      padding: 10px 6px;
      display: grid;
      grid-template-columns: 1fr 1.4fr 1fr;
      grid-template-rows: 1fr 1fr;
      align-items: center;
      justify-items: center;
      box-shadow: 0 3px 10px rgba(0,0,0,0.04);
      min-height: 110px;
    }
    .tile-part {
      font-weight: 700;
      border-radius: 6px;
      padding: 2px 4px;
      transition: all 0.25s ease;
      line-height: 1;
      cursor: pointer;
    }
    .part-a {
      grid-column: 1;
      grid-row: 1;
      font-size: 20px;
      color: #d97706;
      justify-self: end;
    }
    .part-q {
      grid-column: 3;
      grid-row: 1;
      font-size: 22px;
      color: #7c3aed;
      justify-self: start;
    }
    .part-x {
      grid-column: 2;
      grid-row: 1 / span 2;
      font-size: 44px;
      color: #1e2945;
      letter-spacing: -1px;
    }
    .part-z {
      grid-column: 1;
      grid-row: 2;
      font-size: 20px;
      color: #059669;
      justify-self: end;
    }
    .tile-part.highlight {
      transform: scale(1.15);
      filter: brightness(0.9);
      background: rgba(0,0,0,0.04);
    }

    /* Explanation pill */
    .detail-card {
      width: 100%;
      background: #ffffff;
      border: 1.5px solid #e2e8f0;
      border-radius: 10px;
      padding: 10px 12px;
      text-align: center;
      min-height: 48px;
      display: flex;
      flex-direction: column;
      align-items: center;
      justify-content: center;
      gap: 2px;
    }
    .detail-calc {
      font-size: 14px;
      font-weight: 700;
      color: #1e2945;
    }
    .detail-desc {
      font-size: 11px;
      font-weight: 600;
      color: #64748b;
    }
  </style>
</head>
<body>
  <div class="nuclide-board">
    <div class="grid-container">
      
      <button class="badge-btn b-mass active" onclick="setQuadrant(0)">
        <span class="title">Mass (A)</span>
        <span class="formula">p + n</span>
      </button>

      
      <div class="symbol-tile">
        <div class="tile-part part-a highlight" onclick="setQuadrant(0)">35</div>
        <div class="tile-part part-x" onclick="setQuadrant(2)">Cl</div>
        <div class="tile-part part-q" onclick="setQuadrant(1)">−</div>
        <div class="tile-part part-z" onclick="setQuadrant(3)">17</div>
      </div>

      
      <button class="badge-btn b-charge" onclick="setQuadrant(1)">
        <span class="title">Charge (q)</span>
        <span class="formula">p − e</span>
      </button>

      
      <button class="badge-btn b-atomic" onclick="setQuadrant(3)">
        <span class="title">Atomic (Z)</span>
        <span class="formula">protons</span>
      </button>

      
      <button class="badge-btn b-symbol" onclick="setQuadrant(2)">
        <span class="title">Symbol (X)</span>
        <span class="formula">element</span>
      </button>
    </div>

    
    <div class="detail-card" id="detailCard">
      <div class="detail-calc" id="detailCalc" style="color: #d97706;">35 = 17p + 18n</div>
      <div class="detail-desc" id="detailDesc">Total nucleons (protons + neutrons)</div>
    </div>
  </div>

  <script>
    const data = [
      {
        partSel: '.part-a',
        btnSel: '.b-mass',
        color: '#d97706',
        calc: '35 = 17 protons + 18 neutrons',
        desc: 'Mass Number (A = p + n)'
      },
      {
        partSel: '.part-q',
        btnSel: '.b-charge',
        color: '#7c3aed',
        calc: '−1 = 17 protons − 18 electrons',
        desc: 'Net Charge (q = p − e)'
      },
      {
        partSel: '.part-x',
        btnSel: '.b-symbol',
        color: '#1e2945',
        calc: 'Chlorine (17 Protons)',
        desc: 'Chemical Element Symbol (X)'
      },
      {
        partSel: '.part-z',
        btnSel: '.b-atomic',
        color: '#059669',
        calc: '17 = 17 protons',
        desc: 'Atomic Number (Z = p)'
      }
    ];

    let activeIdx = 0;

    function setQuadrant(idx) {
      activeIdx = idx;
      const d = data[idx];

      // Reset buttons and parts
      document.querySelectorAll('.badge-btn').forEach(b => b.classList.remove('active'));
      document.querySelectorAll('.tile-part').forEach(p => p.classList.remove('highlight'));

      // Activate selected
      document.querySelector(d.btnSel).classList.add('active');
      document.querySelector(d.partSel).classList.add('highlight');

      const calcEl = document.getElementById('detailCalc');
      const descEl = document.getElementById('detailDesc');
      calcEl.textContent = d.calc;
      calcEl.style.color = d.color;
      descEl.textContent = d.desc;
    }
  </script>
</body>
</html>

OGS.11.PS.AT.2

Aligned learning resources

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