:root {
    --ink: #14171c;
    --soft: #3a4049;
    --muted: #646b77;
    --line: #dce0e6;
    --canvas: #eef0f3;
    --surface: #f7f8fa;
    --accent: #6e4a14;
  }
  @media (prefers-color-scheme: dark) {
    :root:not([data-theme="light"]) {
      --ink: #e8edf5;
      --soft: #b6c2d2;
      --muted: #8b98a9;
      --line: #26303d;
      --canvas: #0d1219;
      --surface: #131a23;
    }
  }
  * { box-sizing: border-box; }
  body {
    margin: 0;
    background: var(--canvas);
    color: var(--ink);
    font-family: "Archivo", ui-sans-serif, system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
    line-height: 1.65;
    -webkit-font-smoothing: antialiased;
  }
  .masthead {
    border-bottom: 1px solid var(--line);
    background: var(--surface);
  }
  .wrap { max-width: 43rem; margin: 0 auto; padding: 0 1.5rem; }
  .masthead .wrap {
    display: flex; align-items: center; justify-content: space-between;
    gap: 1rem; min-height: 3.5rem; flex-wrap: wrap;
  }
  .brand {
    font-family: "Archivo", ui-sans-serif, system-ui, -apple-system, "Segoe UI", sans-serif;
    font-weight: 600; letter-spacing: -0.01em;
    color: var(--ink); text-decoration: none;
  }
  .masthead nav a { color: var(--muted); text-decoration: none; font-size: .875rem; }
  .masthead nav a:hover { color: var(--accent); text-decoration: underline; }
  header.doc { padding: 3rem 0 2rem; border-bottom: 1px solid var(--line); background: var(--surface); }
  h1 {
    font-family: "Archivo", ui-sans-serif, system-ui, -apple-system, "Segoe UI", sans-serif;
    font-size: clamp(1.85rem, 4.5vw, 2.5rem);
    line-height: 1.15; letter-spacing: -0.02em; margin: 0;
  }
  .intro { margin: 1rem 0 0; font-size: 1.075rem; color: var(--soft); }
  .updated { margin: 1.25rem 0 0; font-size: .875rem; color: var(--muted); }
  main { padding: 2.5rem 0 4rem; }
  section { margin: 0 0 2.25rem; }
  h2 { font-size: 1.075rem; margin: 0 0 .6rem; letter-spacing: -0.005em; }
  p { margin: 0 0 .85rem; color: var(--soft); }
  ul { margin: 0 0 .85rem; padding: 0; list-style: none; }
  li {
    color: var(--soft); border-left: 2px solid var(--line);
    padding: 0 0 0 1rem; margin: 0 0 .6rem;
  }
  a { color: var(--accent); }
  footer {
    border-top: 1px solid var(--line); margin-top: 1rem;
    padding: 1.75rem 0 3rem; font-size: .875rem; color: var(--muted);
  }
  footer p { color: var(--muted); font-size: .875rem; }