/* Header dropdown: single source of truth */
.main-nav {
  align-items: center;
}

.site-header {
  position: sticky;
  top: 0;
  z-index: 120;
  background: transparent !important;
  border-bottom: 1px solid color-mix(in srgb, var(--border) 52%, transparent) !important;
  box-shadow: none !important;
}

.site-header .logo,
.site-header .nav-link,
.site-header .theme-toggle,
.site-header .mobile-menu-btn {
  text-shadow: 0 1px 10px color-mix(in srgb, var(--bg) 72%, transparent);
}

html[data-theme] .site-header {
  background: transparent !important;
  border-bottom-color: color-mix(in srgb, var(--border) 52%, transparent) !important;
  box-shadow: none !important;
}

.header-inner,
.main-nav,
.nav-group,
.nav-group-link,
.header-actions,
.theme-toggle,
.mobile-menu-btn {
  position: relative;
}

.nav-group {
  position: relative;
}

.nav-group summary {
  list-style: none;
  cursor: pointer;
  display: inline-flex;
  align-items: center;
  gap: 6px;
}

.nav-group summary::-webkit-details-marker {
  display: none;
}

.nav-group summary::after {
  content: "▾";
  font-size: 0.72rem;
  opacity: 0.8;
  transition: transform 0.2s ease;
}

.nav-group[open] summary::after {
  transform: rotate(180deg);
}

.nav-group.active > .nav-link,
.nav-group[open] > .nav-link {
  color: var(--text);
  background: color-mix(in srgb, var(--primary) 16%, transparent);
  box-shadow: inset 0 0 0 1px color-mix(in srgb, var(--primary) 38%, transparent);
}

.nav-group-menu {
  position: absolute;
  top: calc(100% + 8px);
  left: 50%;
  right: auto;
  transform: translateX(-50%);
  min-width: 220px;
  max-width: min(92vw, 360px);
  max-height: min(68vh, 420px);
  overflow-y: auto;
  overscroll-behavior: contain;
  display: none;
  padding: 10px;
  border-radius: 20px;
  border: 1px solid var(--border);
  background: color-mix(in srgb, var(--surface-strong) 96%, transparent);
  box-shadow: 0 22px 46px rgba(2, 0, 10, 0.4);
  z-index: 220;
  pointer-events: auto;
}

.nav-group:not([open]) .nav-group-menu {
  display: none !important;
}

.nav-group[open] .nav-group-menu {
  display: grid;
  gap: 6px;
}

.nav-group-link {
  display: block;
  padding: 10px 12px;
  border-radius: 14px;
  color: var(--text-muted);
  font-size: 0.9rem;
  font-weight: 600;
  text-decoration: none;
}

.nav-group-link:hover {
  color: var(--text);
  background: rgba(255, 255, 255, 0.06);
}

.nav-group-link.active {
  color: var(--text);
  background: color-mix(in srgb, var(--primary) 12%, transparent);
}

.mobile-nav-section {
  display: grid;
  gap: 6px;
  margin-top: 12px;
  padding-top: 12px;
  border-top: 1px solid color-mix(in srgb, var(--border) 68%, transparent);
}

.mobile-nav-title {
  padding: 0 16px;
  color: var(--text-muted);
  font-size: 0.76rem;
  font-weight: 800;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

.main-nav > .nav-group:first-of-type .nav-group-menu {
  left: 0;
  transform: none;
}

.main-nav > .nav-group:last-of-type .nav-group-menu {
  right: 0;
  left: auto;
  transform: none;
}

@media (max-width: 1100px) {
  .nav-group-menu {
    left: 0;
    right: auto;
    transform: none;
    max-width: min(92vw, 360px);
  }
}

/* Mobile panel: allow full menu scrolling */
.mobile-nav {
  position: fixed;
  top: 64px;
  left: 0;
  right: 0;
  bottom: 0;
  height: calc(100dvh - 64px);
  min-height: 0;
  max-height: none;
  overflow-y: auto;
  -webkit-overflow-scrolling: touch;
  overscroll-behavior: contain;
  padding-bottom: calc(22px + env(safe-area-inset-bottom));
  z-index: 180;
}

body.nav-open {
  overflow: hidden;
}