*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }

    :root {
      --bg: #0f1117;
      --surface: #1a1d27;
      --border: #252836;
      --accent: #6366f1;
      --accent-dim: rgba(99, 102, 241, 0.14);
      --text-primary: #f1f5f9;
      --text-muted: #94a3b8;
    }

    [data-theme="light"] {
      --bg: #f8fafc;
      --surface: #ffffff;
      --border: #e2e8f0;
      --accent: #4f46e5;
      --accent-dim: rgba(79, 70, 229, 0.12);
      --text-primary: #0f172a;
      --text-muted: #64748b;
    }

    html, body {
      min-height: 100%;
      background: radial-gradient(circle at 12% 0%, rgba(99, 102, 241, 0.14), transparent 55%), var(--bg);
      color: var(--text-primary);
      font-family: 'Inter', system-ui, sans-serif;
      -webkit-font-smoothing: antialiased;
      line-height: 1.55;
    }

    .page { width: min(980px, 94vw); margin: 20px auto 50px; }

    .topbar {
      display: flex;
      align-items: center;
      justify-content: space-between;
      gap: 10px;
      margin-bottom: 16px;
    }

    .top-left {
      display: inline-flex;
      align-items: center;
      gap: 8px;
      flex-wrap: wrap;
    }

    .nav-link,
    .theme-toggle-btn {
      border: 1px solid var(--border);
      background: var(--surface);
      color: var(--text-primary);
      text-decoration: none;
      border-radius: 10px;
      padding: 8px 12px;
      font-size: 13px;
      font-weight: 600;
      display: inline-flex;
      align-items: center;
      gap: 6px;
    }

    .brand-link {
      color: var(--text-primary);
      text-decoration: none;
      font-weight: 700;
      display: inline-flex;
      align-items: center;
      gap: 6px;
      padding: 0;
      border: 0;
      background: transparent;
    }

    .logo-dark { display: block; }
    .logo-light { display: none; }
    [data-theme="light"] .logo-dark { display: none; }
    [data-theme="light"] .logo-light { display: block; }

    .nav-link:hover,
    .theme-toggle-btn:hover {
      border-color: var(--accent);
      background: var(--accent-dim);
    }

    .theme-toggle-btn {
      cursor: pointer;
      font-family: inherit;
      padding: 8px 10px;
      min-width: 40px;
      justify-content: center;
    }

    .theme-icon {
      width: 16px;
      height: 16px;
      display: block;
    }

    .card {
      border: 1px solid var(--border);
      border-radius: 18px;
      background: linear-gradient(145deg, var(--surface), color-mix(in srgb, var(--surface) 86%, #000 14%));
      padding: 24px;
      box-shadow: 0 20px 44px rgba(2, 6, 23, 0.28);
    }

    [data-theme="light"] .card {
      background: linear-gradient(145deg, var(--surface), #f8fbff);
      box-shadow: 0 18px 36px rgba(79, 70, 229, 0.1);
    }

    .kicker {
      font-size: 11px;
      text-transform: uppercase;
      letter-spacing: 0.09em;
      font-weight: 700;
      color: var(--accent);
      margin-bottom: 8px;
    }

    h1 {
      font-size: clamp(1.6rem, 3vw, 2.25rem);
      line-height: 1.15;
      margin-bottom: 8px;
      letter-spacing: -0.5px;
    }

    .intro {
      color: var(--text-muted);
      margin-bottom: 20px;
      max-width: 820px;
    }

    .updated {
      display: inline-flex;
      border: 1px solid var(--border);
      background: var(--accent-dim);
      color: var(--text-primary);
      border-radius: 999px;
      font-size: 12px;
      padding: 6px 10px;
      margin-bottom: 20px;
    }

    .section {
      border-top: 1px solid var(--border);
      padding-top: 18px;
      margin-top: 18px;
    }

    .section h2 {
      font-size: 1.02rem;
      margin-bottom: 9px;
      letter-spacing: -0.2px;
    }

    .section p,
    .section li {
      color: var(--text-muted);
      font-size: 14px;
    }

    .section ul {
      margin-top: 8px;
      padding-left: 18px;
      display: grid;
      gap: 7px;
    }

    a.inline-link {
      color: var(--accent);
      text-underline-offset: 3px;
      text-decoration-thickness: 1.5px;
    }

    @media (max-width: 640px) {
      .page { width: min(980px, 96vw); }
      .card { padding: 18px; }
      .topbar { flex-direction: column; align-items: stretch; }
      .top-left { width: 100%; }
      .theme-toggle-btn { width: 100%; }
    }

.js-display-none:not([style]) {
  display: none;
}