/* Mobile navigation — hamburger + full-screen overlay.
   Injected markup comes from /js/nav.js; this file only styles it.
   Uses the same design tokens as every page (:root vars are defined per page). */

.nav-burger {
  display: none;
  width: 40px;
  height: 40px;
  align-items: center;
  justify-content: center;
  flex-direction: column;
  gap: 5px;
  background: transparent;
  border: 1px solid var(--border, #1b2940);
  border-radius: 9px;
  cursor: pointer;
  padding: 0;
  flex: none;
}
.nav-burger i {
  display: block;
  width: 17px;
  height: 2px;
  border-radius: 1px;
  background: var(--text, #e3ebf5);
  transition: transform .25s cubic-bezier(.2,.8,.3,1), opacity .2s;
}
.nav-burger[aria-expanded="true"] i:nth-child(1) { transform: translateY(7px) rotate(45deg); }
.nav-burger[aria-expanded="true"] i:nth-child(2) { opacity: 0; }
.nav-burger[aria-expanded="true"] i:nth-child(3) { transform: translateY(-7px) rotate(-45deg); }

@media (max-width: 640px) {
  .nav-burger { display: inline-flex; }
  /* header on mobile: logo left, badge + burger right */
  header { justify-content: flex-start; gap: 12px; }
  header .logo { margin-right: auto; }
}

/* ── Overlay ─────────────────────────────────────── */
.nav-overlay {
  position: fixed;
  inset: 0;
  z-index: 300;
  background: rgba(7, 11, 19, .96);
  -webkit-backdrop-filter: blur(18px) saturate(1.3);
  backdrop-filter: blur(18px) saturate(1.3);
  overflow-y: auto;
  overscroll-behavior: contain;
  padding: 76px 26px 48px;
  opacity: 0;
  visibility: hidden;
  transition: opacity .25s ease, visibility 0s .25s;
}
.nav-overlay.open {
  opacity: 1;
  visibility: visible;
  transition: opacity .25s ease;
}
body.nav-locked { overflow: hidden; }

.nav-overlay .nav-close {
  position: fixed;
  top: 10px;
  right: 18px;
  width: 40px;
  height: 40px;
  display: flex;
  align-items: center;
  justify-content: center;
  background: var(--card-bg, #0f1726);
  border: 1px solid var(--border, #1b2940);
  border-radius: 9px;
  color: var(--text, #e3ebf5);
  font-size: 1.15rem;
  line-height: 1;
  cursor: pointer;
}

.nav-group { margin-bottom: 30px; }
.nav-group-label {
  font-family: 'DM Mono', monospace;
  font-size: .64rem;
  letter-spacing: .16em;
  text-transform: uppercase;
  color: var(--accent, #4fa3e8);
  display: flex;
  align-items: center;
  gap: 10px;
  margin-bottom: 13px;
}
.nav-group-label::after {
  content: '';
  flex: 1;
  height: 1px;
  background: var(--border, #1b2940);
}
.nav-group-links {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(150px, 1fr));
  gap: 4px 14px;
}
.nav-group-links a {
  font-family: 'Fraunces', Georgia, serif;
  font-weight: 600;
  font-size: 1.18rem;
  letter-spacing: -.01em;
  color: var(--text, #e3ebf5);
  text-decoration: none;
  padding: 8px 10px;
  border-radius: 8px;
}
.nav-group-links a:active { background: var(--card-bg, #0f1726); }
.nav-group-links a.active {
  color: var(--accent, #4fa3e8);
}
.nav-group-links a.active::after {
  content: '●';
  font-size: .5em;
  vertical-align: middle;
  margin-left: 8px;
}

/* staggered reveal of groups when the overlay opens */
.nav-overlay .nav-group {
  opacity: 0;
  transform: translateY(14px);
  transition: opacity .35s cubic-bezier(.2,.8,.3,1), transform .35s cubic-bezier(.2,.8,.3,1);
}
.nav-overlay.open .nav-group { opacity: 1; transform: translateY(0); }
.nav-overlay.open .nav-group:nth-child(2) { transition-delay: .04s; }
.nav-overlay.open .nav-group:nth-child(3) { transition-delay: .08s; }
.nav-overlay.open .nav-group:nth-child(4) { transition-delay: .12s; }
.nav-overlay.open .nav-group:nth-child(5) { transition-delay: .16s; }
.nav-overlay.open .nav-group:nth-child(6) { transition-delay: .2s; }

.nav-overlay-foot {
  font-family: 'DM Mono', monospace;
  font-size: .62rem;
  letter-spacing: .12em;
  text-transform: uppercase;
  color: var(--dim, #3d5270);
  margin-top: 10px;
}

@media (prefers-reduced-motion: reduce) {
  .nav-burger i,
  .nav-overlay,
  .nav-overlay .nav-group { transition: none !important; }
}