/* ========== BASE & RESET ========== */
  *, *::before, *::after {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
  }

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

  body {
    font-family: 'Inter', sans-serif;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
  }

  img {
    max-width: 100%;
    height: auto;
  }

  ::selection {
    background: #34d399;
    color: #0f172a;
  }

  /* ========== NAVBAR ========== */
  #navbar {
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
  }

  #navbar.scrolled {
    background: rgba(15, 23, 42, 0.95);
    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: 2px;
    background: #34d399;
    transition: width 0.3s ease;
  }

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

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

  #mobileMenu.closed {
    opacity: 0;
    pointer-events: none;
  }

  .menu-line {
    display: block;
  }

  body.menu-open {
    overflow: hidden;
  }

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

  /* ========== SECTION TRANSITIONS ========== */
  section {
    position: relative;
  }

  /* ========== SCROLL REVEAL (progressive enhancement) ========== */
  @media (prefers-reduced-motion: no-preference) {
    .reveal {
      opacity: 0;
      transform: translateY(30px);
      transition: opacity 0.8s ease, transform 0.8s 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; }
    .reveal-delay-4 { transition-delay: 0.4s; }
  }

  /* ========== BUTTON HOVER EFFECTS ========== */
  a, button {
    transition: all 0.2s ease;
  }

  /* ========== CUSTOM SCROLLBAR ========== */
  ::-webkit-scrollbar {
    width: 8px;
  }

  ::-webkit-scrollbar-track {
    background: #0f172a;
  }

  ::-webkit-scrollbar-thumb {
    background: #334155;
    border-radius: 4px;
  }

  ::-webkit-scrollbar-thumb:hover {
    background: #34d399;
  }

  /* ========== RESPONSIVE ========== */
  @media (max-width: 768px) {
    html {
      scroll-padding-top: 70px;
    }

    #hero h1 {
      font-size: 3.5rem;
    }

    .font-display {
      letter-spacing: 0.02em;
    }
  }

  @media (max-width: 640px) {
    #hero h1 {
      font-size: 2.75rem;
    }
  }