:root {
    --bg: #0b0f14;
    --card: #121821;
    --text: #e8eef6;
    --muted: #b9c3cf;
    --brand: #66e3ff;
    --brand-2: #6df3c1;
    --border: #1f2a38;
    --accent: #98ffe0;
    --maxw: 72rem;
  }
  html { scroll-behavior: smooth; }
  body {
    margin: 0; font-family: system-ui, -apple-system, Segoe UI, Roboto, Ubuntu, "Helvetica Neue", Arial, "Noto Sans", sans-serif;
    background: linear-gradient(180deg, #091017 0%, #0b0f14 100%);
    color: var(--text);
  }
  .container { max-width: var(--maxw); margin: 0 auto; padding: 2rem 1.25rem; }
  header.site { display: flex; align-items: center; justify-content: space-between; padding: 1rem 0; border-bottom: 1px solid var(--border); }
  header.site a.logo { text-decoration: none; color: var(--text); font-weight: 700; letter-spacing: .3px; }
  header.site nav a { color: var(--muted); text-decoration: none; margin-left: 1rem; }
  .hero { padding: 2rem 0 1rem; margin-bottom: .5rem; }
  .eyebrow { color: var(--brand); font-weight: 600; text-transform: uppercase; letter-spacing: .12em; font-size: .78rem; }
  h1 {
    font-size: clamp(2rem, 4vw, 3rem);
    line-height: 1.1; margin: .5rem 0 1rem;
    background: linear-gradient(90deg, var(--brand), var(--brand-2));
    -webkit-background-clip: text; background-clip: text; color: transparent;
  }
  .subhead { color: var(--muted); font-size: 1.1rem; max-width: 60ch; }
  .cta-wrap { margin-top: 1.5rem; display: flex; gap: .75rem; flex-wrap: wrap; }
  .btn {
    display: inline-block; padding: .8rem 1.05rem; border-radius: .9rem; text-decoration: none; font-weight: 600;
    border: 1px solid var(--border); color: var(--text); background: #0e141c;
  }
  .btn.primary { background: linear-gradient(90deg, var(--brand), var(--brand-2)); color: #041014; border: none; }
  .btn.ghost { color: var(--muted); }
  article { background: var(--card); border: 1px solid var(--border); border-radius: 1.2rem; padding: 1.5rem; }
  article h2 { margin-top: 2rem; font-size: clamp(1.3rem, 2.5vw, 1.75rem); }
  article h3 { margin-top: 1.5rem; }
  article p { color: var(--text); line-height: 1.7; }
  article ul { padding-left: 1.25rem; }
  article li { margin: .4rem 0; }
  .toc {
    margin: 1rem 0 2rem; background: #0f1620; border: 1px solid var(--border);
    border-radius: .8rem; padding: 1rem;
  }
  .toc a { color: var(--accent); text-decoration: none; }
  .meta { display: grid; gap: .35rem; color: var(--muted); margin: .75rem 0 1.25rem; font-size: .95rem; }
  .note {
    border-left: 3px solid var(--brand); padding: .75rem 1rem; background: #0f1620; border-radius: .5rem; color: var(--muted);
  }
  footer.site { opacity: .9; color: var(--muted); padding: 2rem 0; text-align: center; }
  .kbd { font-family: ui-monospace, SFMono-Regular, Menlo, Consolas, "Liberation Mono", monospace; font-size: .92em; background: #0d131b; border: 1px solid var(--border); padding: .1rem .4rem; border-radius: .35rem; color: var(--text); }
  .prose { max-width: 70ch; }
  @media (min-width: 960px) {
    .grid { display: grid; grid-template-columns: 1.2fr .8fr; gap: 2rem; align-items: start; }
    .aside-card { position: sticky; top: 1rem; }
  }
  .aside-card { background: #0f1620; border: 1px solid var(--border); border-radius: 1rem; padding: 1rem; }
  .full-width { width: 100%; height: auto; }