:root {
      --bg: #07131a;
      --bg2: #0b1d26;
      --panel: rgba(255,255,255,0.06);
      --panel-border: rgba(255,255,255,0.12);
      --text: #eef7fb;
      --muted: #b9cad3;
      --accent: #49c2ff;
      --accent2: #4de0b7;
      --maxw: 920px;
      --radius: 18px;
      --shadow: 0 18px 50px rgba(0,0,0,.35);
    }

    * { box-sizing: border-box; }
    html { scroll-behavior: smooth; }
    body {
      margin: 0;
      font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
      color: var(--text);
      background:
        radial-gradient(circle at top left, rgba(77,224,183,.12), transparent 28%),
        radial-gradient(circle at top right, rgba(73,194,255,.14), transparent 30%),
        linear-gradient(180deg, var(--bg2), var(--bg));
      line-height: 1.6;
    }

    a {
      color: var(--accent);
      text-decoration: none;
    }
    a:hover { text-decoration: underline; }

    .wrap {
      max-width: var(--maxw);
      margin: 0 auto;
      padding: 28px 18px 56px;
    }

    .hero {
      padding: 28px;
      border: 1px solid var(--panel-border);
      border-radius: 24px;
      background: linear-gradient(180deg, rgba(255,255,255,.07), rgba(255,255,255,.04));
      box-shadow: var(--shadow);
      backdrop-filter: blur(8px);
    }

    .eyebrow {
      display: inline-block;
      font-size: 12px;
      letter-spacing: .12em;
      text-transform: uppercase;
      color: var(--accent2);
      margin-bottom: 10px;
      font-weight: 700;
    }

    h1, h2, h3 {
      line-height: 1.2;
      margin: 0 0 12px;
    }
    h1 {
      font-size: clamp(2rem, 4vw, 3rem);
      margin-bottom: 14px;
    }
    h2 {
      font-size: 1.45rem;
      margin-bottom: 14px;
    }
    h3 {
      font-size: 1.05rem;
      margin-bottom: 8px;
    }

    p, li { color: var(--muted); }
    .hero p.lead {
      font-size: 1.06rem;
      max-width: 70ch;
    }

    .cta-row {
      display: flex;
      flex-wrap: wrap;
      gap: 12px;
      margin-top: 18px;
    }

    .btn {
      display: inline-flex;
      align-items: center;
      justify-content: center;
      min-height: 44px;
      padding: 0 16px;
      border-radius: 12px;
      border: 1px solid var(--panel-border);
      background: rgba(255,255,255,.05);
      color: var(--text);
      font-weight: 600;
    }

    .btn.primary {
      background: linear-gradient(135deg, rgba(73,194,255,.20), rgba(77,224,183,.18));
      border-color: rgba(77,224,183,.35);
    }

    .grid {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 18px;
      margin-top: 22px;
    }

    .panel {
      border: 1px solid var(--panel-border);
      border-radius: var(--radius);
      background: var(--panel);
      box-shadow: var(--shadow);
      padding: 22px;
    }

    .panel.full { grid-column: 1 / -1; }

    ul {
      margin: 0;
      padding-left: 18px;
    }

    .toc {
      display: flex;
      flex-wrap: wrap;
      gap: 10px;
      margin-top: 18px;
    }

    .toc a {
      padding: 8px 12px;
      border-radius: 999px;
      border: 1px solid var(--panel-border);
      background: rgba(255,255,255,.04);
      color: var(--text);
      font-size: .95rem;
    }

    .note {
      border-left: 4px solid var(--accent2);
      padding: 10px 14px;
      background: rgba(255,255,255,.04);
      border-radius: 10px;
      margin-top: 14px;
    }

    .small {
      font-size: .95rem;
    }

    footer {
      margin-top: 22px;
      text-align: center;
      color: #93a8b3;
      font-size: .92rem;
    }

    code {
      font-family: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
      font-size: .95em;
      color: #d5f4ff;
    }

    @media (max-width: 760px) {
      .grid { grid-template-columns: 1fr; }
      .panel.full { grid-column: auto; }
      .hero { padding: 22px; }
    }