/* ── Base ── */
*, *::before, *::after { box-sizing: border-box; }
html { scroll-behavior: smooth; scroll-padding-top: 80px; }
body { margin: 0; -webkit-font-smoothing: antialiased; }
img, svg { display: block; max-width: 100%; }
a { text-decoration: none; color: inherit; }
button { cursor: pointer; border: none; background: none; font-family: inherit; }
ul, ol { list-style: none; padding: 0; margin: 0; }

/* ── Scroll-reveal (progressive enhancement) ── */
@media (prefers-reduced-motion: no-preference) {
  .reveal {
    opacity: 0;
    transform: translateY(28px);
    transition: opacity 0.7s cubic-bezier(0.22, 1, 0.36, 1), transform 0.7s cubic-bezier(0.22, 1, 0.36, 1);
  }
  .reveal.revealed {
    opacity: 1;
    transform: translateY(0);
  }
}
@supports not (animation-timing-function: cubic-bezier(0.22, 1, 0.36, 1)) {
  .reveal { transition-duration: 0.5s; }
}

/* ── Header ── */
#site-header {
  background: transparent;
  transition: background 0.35s, box-shadow 0.35s, backdrop-filter 0.35s;
}
#site-header.scrolled {
  background: rgba(2, 6, 23, 0.88);
  backdrop-filter: blur(16px) saturate(180%);
  -webkit-backdrop-filter: blur(16px) saturate(180%);
  box-shadow: 0 1px 0 rgba(255,255,255,0.06);
}

.nav-link { position: relative; }
.nav-link::after {
  content: '';
  position: absolute;
  bottom: -2px;
  left: 0;
  width: 0;
  height: 2px;
  background: #2dd4bf;
  border-radius: 1px;
  transition: width 0.25s;
}
.nav-link:hover::after { width: 100%; }

/* ── Buttons ── */
.btn-primary, .btn-secondary {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.75rem 1.75rem;
  border-radius: 1rem;
  font-weight: 600;
  font-size: 1rem;
  transition: transform 0.2s, box-shadow 0.2s, background-color 0.2s;
}

/* ── Hero ── */
.hero {
  background:
    url('https://images.pexels.com/photos/4712152/pexels-photo-4712152.jpeg?auto=compress&cs=tinysrgb&fit=crop&w=1920&h=1080')
    center center / cover no-repeat;
  position: relative;
}
.hero-overlay {
  background: linear-gradient(
    135deg,
    rgba(2, 6, 23, 0.82) 0%,
    rgba(4, 47, 46, 0.72) 50%,
    rgba(15, 118, 110, 0.55) 100%
  );
}
.hero-pattern {
  background-image: radial-gradient(circle at 1px 1px, rgba(255,255,255,0.08) 1px, transparent 0);
  background-size: 32px 32px;
}
.hero-img-wrapper { position: relative; }
.scroll-indicator { opacity: 0.6; }
.scroll-indicator:hover { opacity: 1; }

/* ── Mobile menu ── */
#mobile-menu {
  animation: slideDown 0.25s ease-out;
}
@keyframes slideDown {
  from { opacity: 0; transform: translateY(-8px); }
  to   { opacity: 1; transform: translateY(0); }
}
.mobile-nav-link { display: block; }

/* ── Utility ── */
.sr-only {
  position: absolute; width: 1px; height: 1px;
  padding: 0; margin: -1px; overflow: hidden;
  clip: rect(0,0,0,0); white-space: nowrap; border: 0;
}