/* ===== Header / Nav ===== */
      header.site-header {
        position: sticky;
        top: 0;
        z-index: 50;
        background: rgba(17, 21, 27, 0.7);
        backdrop-filter: blur(var(--blur));
        border-bottom: 1px solid var(--border);
      }
      @media (prefers-color-scheme: light) {
        header.site-header {
          background: rgba(255, 255, 255, 0.7);
        }
      }
      .nav {
        display: flex;
        align-items: center;
        justify-content: space-between;
        gap: 1rem;
        height: 64px;
      }
      .nav a.logo {
        font-weight: 800;
        letter-spacing: 0.3px;
      }
      .nav ul {
        display: flex;
        gap: 0.75rem;
        list-style: none;
        margin: 0;
        padding: 0;
      }
      .nav a.navlink {
        padding: 0.6rem 0.9rem;
        border-radius: 999px;
        display: inline-flex;
        align-items: center;
        gap: 0.5rem;
        border: 1px solid transparent;
      }
      .nav a.navlink:hover {
        background: var(--chip);
        border-color: var(--border);
      }
      .cta {
        padding: 0.6rem 0.95rem;
        border-radius: 999px;
        background: linear-gradient(135deg, var(--primary), var(--primary-2));
        font-weight: 600;
      }