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

  html {
    scroll-behavior: smooth;
    scroll-padding-top: 80px;
  }

  body {
    overflow-x: hidden;
  }

  /* NAV */
  #nav {
    transition: background-color 0.4s ease, box-shadow 0.4s ease, padding 0.4s ease;
  }

  #nav.scrolled {
    background-color: rgba(2, 6, 23, 0.95);
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    box-shadow: 0 1px 0 rgba(255, 255, 255, 0.05);
  }

  .nav-link {
    position: relative;
  }

  .nav-link::after {
    content: '';
    position: absolute;
    bottom: -4px;
    left: 0;
    width: 0;
    height: 1px;
    background-color: #2dd4bf;
    transition: width 0.3s ease;
  }

  .nav-link:hover::after {
    width: 100%;
  }

  /* MOBILE MENU */
  #mobile-menu.open {
    opacity: 1;
    pointer-events: all;
  }

  .mobile-link {
    opacity: 0;
    transform: translateY(10px);
    transition: opacity 0.3s ease, transform 0.3s ease, color 0.3s ease;
  }

  #mobile-menu.open .mobile-link {
    opacity: 1;
    transform: translateY(0);
  }

  #mobile-menu.open .mobile-link:nth-child(1) { transition-delay: 0.1s; }
  #mobile-menu.open .mobile-link:nth-child(2) { transition-delay: 0.15s; }
  #mobile-menu.open .mobile-link:nth-child(3) { transition-delay: 0.2s; }
  #mobile-menu.open .mobile-link:nth-child(4) { transition-delay: 0.25s; }
  #mobile-menu.open .mobile-link:nth-child(5) { transition-delay: 0.3s; }

  /* HERO */
  #hero {
    position: relative;
  }

  /* SCROLL REVEAL */
  .reveal {
    opacity: 0;
    transform: translateY(30px);
    transition: opacity 0.8s cubic-bezier(0.25, 0.46, 0.45, 0.94), transform 0.8s cubic-bezier(0.25, 0.46, 0.45, 0.94);
  }

  .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; }
  .reveal-delay-4 { transition-delay: 0.4s; }

  /* BACK TO TOP */
  #back-to-top.visible {
    opacity: 1;
    pointer-events: all;
  }

  /* REDUCED MOTION */
  @media (prefers-reduced-motion: reduce) {
    html {
      scroll-behavior: auto;
    }
    .reveal {
      opacity: 1;
      transform: none;
      transition: none;
    }
    .nav-link::after {
      display: none;
    }
    #back-to-top {
      transition: none;
    }
  }

  /* 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;
  }

  /* SELECT STYLING */
  select option {
    background: white;
    color: #1e293b;
  }