/* ─── Base & Utilities ─── */
  *, *::before, *::after { box-sizing: border-box; }
  html { scroll-behavior: smooth; scroll-padding-top: 80px; }
  body { margin: 0; }
  img { display: block; max-width: 100%; }
  a { text-decoration: none; }
  ::selection { background: rgba(20,184,166,0.3); color: #f0fdfa; }

  /* ─── Navbar ─── */
  #navbar { transition: background 0.4s, box-shadow 0.4s, backdrop-filter 0.4s; }
  #navbar.scrolled {
    background: rgba(2,6,23,0.85);
    backdrop-filter: blur(16px);
    box-shadow: 0 1px 0 rgba(255,255,255,0.05);
  }

  /* ─── Menu Tabs ─── */
  .menu-tab.active {
    border-color: rgb(13,148,136) !important;
    background: rgb(13,148,136) !important;
    color: #fff !important;
  }
  .menu-tab:not(.active):hover {
    border-color: rgba(45,212,191,0.5) !important;
    color: rgb(134,239,221) !important;
    background: rgba(13,148,136,0.08) !important;
  }

  /* ─── Scroll Animations ─── */
  .reveal {
    opacity: 0;
    transform: translateY(32px);
    transition: opacity 0.7s cubic-bezier(0.16,1,0.3,1), transform 0.7s cubic-bezier(0.16,1,0.3,1);
  }
  .reveal.visible {
    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; }

  /* ─── Mobile Menu Transition ─── */
  #mobile-menu {
    max-height: 0;
    overflow: hidden;
    transition: max-height 0.4s cubic-bezier(0.16,1,0.3,1);
  }
  #mobile-menu.open {
    max-height: 400px;
  }

  /* ─── Custom Scrollbar ─── */
  ::-webkit-scrollbar { width: 8px; }
  ::-webkit-scrollbar-track { background: #0f172a; }
  ::-webkit-scrollbar-thumb { background: #1e293b; border-radius: 4px; }
  ::-webkit-scrollbar-thumb:hover { background: #334155; }

  /* ─── Geometric Shape Decorations ─── */
  .geo-diamond {
    position: absolute;
    width: 64px;
    height: 64px;
    background: rgba(13,148,136,0.08);
    border: 1px solid rgba(13,148,136,0.15);
    transform: rotate(45deg);
    pointer-events: none;
  }

  /* ─── Hero Text Gradient ─── */
  .text-gradient {
    background: linear-gradient(135deg, #2dd4bf 0%, #5eead4 50%, #99f6e4 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
  }