/* ── Base & Utilities ── */
  *, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
  html { scroll-behavior: smooth; scroll-padding-top: 80px; }
  body { overflow-x: hidden; }

  /* ── Header scroll state ── */
  #site-header {
    background: transparent;
    transition: background 0.3s ease, box-shadow 0.3s ease, backdrop-filter 0.3s ease;
  }
  #site-header.scrolled {
    background: rgba(6, 18, 36, 0.92);
    backdrop-filter: blur(16px);
    box-shadow: 0 1px 0 rgba(255,255,255,0.06);
  }

  /* ── Nav links ── */
  .nav-link { position: relative; }
  .nav-link::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 50%;
    width: 0;
    height: 2px;
    background: #D4A84B;
    transition: width 0.2s ease, left 0.2s ease;
  }
  .nav-link:hover::after { width: 60%; left: 20%; }

  /* ── Mobile menu ── */
  #mobile-menu {
    animation: slideDown 0.25s ease forwards;
  }
  @keyframes slideDown {
    from { opacity: 0; transform: translateY(-8px); }
    to   { opacity: 1; transform: translateY(0); }
  }
  #mobile-menu.hidden { display: none; }

  /* Hamburger animation */
  #menu-toggle[aria-expanded="true"] #hamburger span:first-child {
    transform: translateY(4px) rotate(45deg);
  }
  #menu-toggle[aria-expanded="true"] #hamburger span:nth-child(2) {
    opacity: 0;
  }
  #menu-toggle[aria-expanded="true"] #hamburger span:last-child {
    width: 100%;
    transform: translateY(-4px) rotate(-45deg);
  }

  .mobile-nav-link { display: block; }

  /* ── Scroll reveal (progressive enhancement) ── */
  @media (prefers-reduced-motion: no-preference) {
    .reveal {
      opacity: 0;
      transform: translateY(24px);
      transition: opacity 0.6s ease, transform 0.6s ease;
    }
    .reveal.revealed {
      opacity: 1;
      transform: translateY(0);
    }
    .reveal-delay-1 { transition-delay: 0.1s; }
    .reveal-delay-2 { transition-delay: 0.2s; }
    .reveal-delay-3 { transition-delay: 0.3s; }
  }

  /* ── Focus styles ── */
  a:focus-visible, button:focus-visible, input:focus-visible, textarea:focus-visible {
    outline: 2px solid #D4A84B;
    outline-offset: 2px;
  }

  /* ── Selection ── */
  ::selection { background: rgba(212, 168, 75, 0.3); color: #fff; }

  /* ── Custom scrollbar ── */
  ::-webkit-scrollbar { width: 8px; }
  ::-webkit-scrollbar-track { background: #0A1F3F; }
  ::-webkit-scrollbar-thumb { background: #2E5E8F; border-radius: 4px; }
  ::-webkit-scrollbar-thumb:hover { background: #D4A84B; }