Attribute inheritance & Participation inheritance

<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>Domain Tree Hierarchy</title>
<style>
.infographic-domtree {
  --ink:        #1a1a1a;
  --ink-soft:   #5c5c5c;
  --paper:      #ffffff;
  --paper-alt:  #f0ece4;
  --accent:     #2563eb;
  --accent-soft:#e3ebfd;
  --line:       #ddd6c9;
  --display-font: Georgia, 'Iowan Old Style', serif;
  --body-font: -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  --mono-font: 'SF Mono', Consolas, monospace;

  background: var(--paper);
  color: var(--ink);
  font-family: var(--body-font);
  max-width: 1180px;
  margin: 0 auto;
  box-sizing: border-box;
}
.infographic-domtree[data-theme="dark"] {
  --ink:        #e8e6e1;
  --ink-soft:   #9a968c;
  --paper:      #121212;
  --paper-alt:  #1e1e26;
  --accent:     #5b8def;
  --accent-soft:#202942;
  --line:       #2c313d;
}
.infographic-domtree * { box-sizing: border-box; }

.dt-head { text-align: center; margin-bottom: 0.25rem; }
.dt-head h2 {
  font-family: var(--display-font);
  font-size: 2.1rem;
  margin: 0 0 0.5rem;
  letter-spacing: -0.01em;
}
.dt-head p {
  color: var(--ink-soft);
  font-size: 1.08rem;
  margin: 0 auto;
  max-width: 560px;
}

.dt-body {
  display: grid;
  grid-template-columns: 1fr 260px;
  gap: 2.25rem;
  align-items: start;
  margin-top: 2.25rem;
}
@media (max-width: 780px) {
  .dt-body { grid-template-columns: 1fr; }
}

.dt-svg-wrap {
  background: var(--paper-alt);
  border: 1px solid var(--line);
  border-radius: 10px;
  padding: 1.5rem 1rem 1rem;
}

.dt-node circle {
  fill: var(--paper);
  stroke: var(--line);
  stroke-width: 1.5;
  cursor: pointer;
  transition: stroke 0.15s, fill 0.15s, opacity 0.15s;
}
.dt-node text {
  fill: var(--ink);
  font-size: 16px;
  font-family: var(--body-font);
  pointer-events: none;
  transition: fill 0.15s, opacity 0.15s;
}
.dt-node .dt-sub {
  fill: var(--ink-soft);
  font-size: 12.5px;
}
.dt-edge {
  stroke: var(--line);
  stroke-width: 2;
  transition: stroke 0.15s, stroke-width 0.15s, opacity 0.15s;
}

.dt-node.is-dim circle,
.dt-node.is-dim text { opacity: 0.35; }
.dt-edge.is-dim { opacity: 0.3; }

.dt-node.is-active circle {
  stroke: var(--accent);
  stroke-width: 3.5;
  fill: var(--accent-soft);
}
.dt-node.is-active text { fill: var(--accent); }
.dt-node.is-root.is-active circle { fill: var(--accent); }
.dt-node.is-root.is-active text { fill: var(--paper); }

.dt-edge.is-active {
  stroke: var(--accent);
  stroke-width: 3.5;
}

.dt-node.is-root:not(.is-active) circle { fill: var(--paper-alt); stroke-width: 2; }

.dt-panel {
  background: var(--paper-alt);
  border: 1px solid var(--line);
  border-radius: 10px;
  padding: 1.1rem 1.2rem;
  min-height: 240px;
}
.dt-panel .dt-panel-title {
  font-family: var(--display-font);
  font-size: 1.15rem;
  margin: 0 0 0.2rem;
  color: var(--accent);
}
.dt-panel .dt-panel-role {
  font-size: 0.78rem;
  text-transform: uppercase;
  letter-spacing: 0.04em;
  color: var(--ink-soft);
  margin: 0 0 0.85rem;
}
.dt-panel .dt-panel-chain {
  font-family: var(--mono-font);
  font-size: 0.85rem;
  color: var(--ink);
  background: var(--paper);
  border: 1px solid var(--line);
  border-radius: 6px;
  padding: 0.55rem 0.7rem;
  margin: 0 0 0.85rem;
  line-height: 1.5;
  word-break: break-word;
}
.dt-panel .dt-panel-desc {
  font-size: 0.88rem;
  color: var(--ink-soft);
  line-height: 1.5;
  margin: 0;
}
.dt-panel .dt-hint {
  font-size: 0.88rem;
  color: var(--ink-soft);
  line-height: 1.5;
}


@media (prefers-reduced-motion: reduce) {
  .infographic-domtree *, .infographic-domtree *::before, .infographic-domtree *::after {
    transition-duration: 0.001ms !important;
    animation-duration: 0.001ms !important;
  }
}
</style>
</head>
<body>

<div class="infographic-domtree" id="domtree">

  <div class="dt-head">
    <h2>Domain Tree Hierarchy</h2>
    <p>Click any domain to trace its trust path back to the forest root.</p>
  </div>

  <div class="dt-body">
    <div class="dt-svg-wrap">
      <svg viewBox="0 0 900 440" width="100%" role="img" aria-label="Domain tree diagram">
        <!-- edges -->
        <line class="dt-edge" data-edge="A-B" x1="450" y1="90" x2="270" y2="215"></line>
        <line class="dt-edge" data-edge="A-F" x1="450" y1="90" x2="640" y2="215"></line>
        <line class="dt-edge" data-edge="B-C" x1="270" y1="215" x2="110" y2="350"></line>
        <line class="dt-edge" data-edge="B-D" x1="270" y1="215" x2="305" y2="350"></line>
        <line class="dt-edge" data-edge="F-G" x1="640" y1="215" x2="760" y2="350"></line>

        <!-- Domain A / root -->
        <g class="dt-node is-root" data-id="A" tabindex="0" role="button" aria-label="Domain A, My underscore MSP, forest root">
          <circle cx="450" cy="90" r="55"></circle>
          <text x="450" y="85" text-anchor="middle">Domain A</text>
          <text x="450" y="104" text-anchor="middle" class="dt-sub">My_MSP</text>
        </g>

        <!-- Domain B -->
        <g class="dt-node" data-id="B" tabindex="0" role="button" aria-label="Domain B">
          <circle cx="270" cy="215" r="49"></circle>
          <text x="270" y="221" text-anchor="middle">Domain B</text>
        </g>

        <!-- Domain F -->
        <g class="dt-node" data-id="F" tabindex="0" role="button" aria-label="Domain F">
          <circle cx="640" cy="215" r="49"></circle>
          <text x="640" y="221" text-anchor="middle">Domain F</text>
        </g>

        <!-- Domain C -->
        <g class="dt-node" data-id="C" tabindex="0" role="button" aria-label="Domain C">
          <circle cx="110" cy="350" r="45"></circle>
          <text x="110" y="356" text-anchor="middle">Domain C</text>
        </g>

        <!-- Domain D -->
        <g class="dt-node" data-id="D" tabindex="0" role="button" aria-label="Domain D">
          <circle cx="305" cy="350" r="45"></circle>
          <text x="305" y="356" text-anchor="middle">Domain D</text>
        </g>

        <!-- Domain G -->
        <g class="dt-node" data-id="G" tabindex="0" role="button" aria-label="Domain G">
          <circle cx="760" cy="350" r="45"></circle>
          <text x="760" y="356" text-anchor="middle">Domain G</text>
        </g>
      </svg>
    </div>

    <div class="dt-panel" id="dtPanel">
      <p class="dt-hint">Select a domain node to see its position in the tree and its trust chain up to the root.</p>
    </div>
  </div>


</div>

<script>
(function () {
  // Dark mode detection — priority: body attribute, then cookie
  const wrapper = document.getElementById('domtree');
  const bodyAttr = document.body.getAttribute('data-darkmode');
  let dark;
  if (bodyAttr === 'true') {
    dark = true;
  } else if (bodyAttr === 'false') {
    dark = false;
  } else {
    const match = document.cookie.match(/(?:^|;\s*)darkMode=([^;]+)/);
    dark = match ? match[1] === 'true' : false;
  }
  if (dark) wrapper.setAttribute('data-theme', 'dark');
})();

(function () {
  // Tree structure: parent map + info per domain
  const parent = { A: null, B: 'A', F: 'A', C: 'B', D: 'B', G: 'F' };
  const info = {
    A: { role: 'Forest root domain', desc: 'Top of the namespace. Every domain in the forest ultimately trusts A. Managed as My_MSP.' },
    B: { role: 'Child domain of A', desc: 'Shares a two-way transitive trust with A. Parent to C and D.' },
    F: { role: 'Child domain of A', desc: 'Shares a two-way transitive trust with A. Parent to G.' },
    C: { role: 'Child domain of B (grandchild of A)', desc: 'Trusts B directly, and A transitively through B.' },
    D: { role: 'Child domain of B (grandchild of A)', desc: 'Trusts B directly, and A transitively through B.' },
    G: { role: 'Child domain of F (grandchild of A)', desc: 'Trusts F directly, and A transitively through F.' }
  };

  const nodes = document.querySelectorAll('.dt-node');
  const edges = document.querySelectorAll('.dt-edge');
  const panel = document.getElementById('dtPanel');

  function pathToRoot(id) {
    const chain = [id];
    let cur = id;
    while (parent[cur]) {
      cur = parent[cur];
      chain.push(cur);
    }
    return chain.reverse(); // root first
  }

  function edgeKeyBetween(a, b) {
    return [a + '-' + b, b + '-' + a];
  }

  function select(id) {
    const chain = pathToRoot(id); // e.g. ['A','B','C']
    const chainSet = new Set(chain);

    nodes.forEach(n => {
      const nid = n.dataset.id;
      n.classList.toggle('is-active', chainSet.has(nid));
      n.classList.toggle('is-dim', !chainSet.has(nid));
    });

    edges.forEach(e => {
      const [x, y] = e.dataset.edge.split('-');
      const onPath = chain.includes(x) && chain.includes(y) &&
        Math.abs(chain.indexOf(x) - chain.indexOf(y)) === 1;
      e.classList.toggle('is-active', onPath);
      e.classList.toggle('is-dim', !onPath);
    });

    const meta = info[id];
    const chainLabel = chain.map(c => c === 'A' ? 'A (My_MSP)' : c).join(' → ');
    panel.innerHTML =
      '<p class="dt-panel-title">Domain ' + id + '</p>' +
      '<p class="dt-panel-role">' + meta.role + '</p>' +
      '<p class="dt-panel-chain">' + chainLabel + '</p>' +
      '<p class="dt-panel-desc">' + meta.desc + '</p>';
  }

  nodes.forEach(n => {
    n.addEventListener('click', () => select(n.dataset.id));
    n.addEventListener('keydown', (e) => {
      if (e.key === 'Enter' || e.key === ' ') {
        e.preventDefault();
        select(n.dataset.id);
      }
    });
  });
})();
</script>

</body>
</html>

.demo {
  font-family: system-ui, sans-serif;
  padding: 16px;
}

.demo h1 {
  color: #2563eb;
  margin: 0 0 8px;
}

.demo p {
  color: #4b5563;
  margin: 0;
}

document.querySelector('.demo h1')?.addEventListener('click', () => {
  alert('Hello from live preview!');
});