/* ════════════════════════════════════════════════════════════════
   NAV
════════════════════════════════════════════════════════════════ */
nav {
  position: fixed;
  top: 0; left: 0; right: 0;
  height: 60px;
  display: grid;
  grid-template-columns: 1fr auto 1fr;
  align-items: center;
  padding: 0 28px;
  background: transparent;
  border-bottom: 1px solid transparent;
  backdrop-filter: blur(0px);
  -webkit-backdrop-filter: blur(0px);
  transition:
    background 0.4s ease,
    border-color 0.4s ease,
    backdrop-filter 0.4s ease;
  z-index: 200;
}

.nav-logo-link { justify-self: start; display: flex; align-items: center; cursor: pointer; }
.nav-logo-link:focus-visible { outline: 2px solid var(--brand-gold); outline-offset: 3px; border-radius: var(--radius-sm); }
.nav-tabs { justify-self: center; }
.nav-right-group { justify-self: end; display: flex; align-items: center; gap: 8px; }
.theme-toggle { /* inside .nav-right-group */ }

/* ── Surface-aware nav: auto-detects light/dark surface beneath it.
   Completely exempt from the theme toggle — uses hardcoded colors
   so it looks correct over forced-dark hero AND themed panels.
   Surface class controls TEXT colors (always applied).
   Glass class controls backdrop blur + bg (always on). ── */

nav.nav--glass {
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
}

/* Dark surface + glass → dark translucent glass bg */
nav.nav--dark-surface.nav--glass {
  background: rgba(9,9,11,0.65);
  border-bottom-color: rgba(255,255,255,0.07);
}

/* Dark surface WITHOUT glass → still show subtle bg so blur has content */
nav.nav--dark-surface {
  background: rgba(9,9,11,0.45);
}

nav.nav--dark-surface .nav-logo {
  filter: none;
}

nav.nav--dark-surface .exp-tabs {
  background: rgba(255,255,255,0.06);
  border-color: rgba(255,255,255,0.10);
}

nav.nav--dark-surface .exp-tab {
  color: rgba(255,255,255,0.50);
}

nav.nav--dark-surface .exp-tab.active {
  background: rgba(255,255,255,0.11);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  color: rgba(255,255,255,0.95);
}

nav.nav--dark-surface .exp-tab:hover:not(.active) {
  color: rgba(255,255,255,0.80);
  background: rgba(255,255,255,0.05);
}

/* Light surface + glass → light translucent glass bg */
nav.nav--light-surface.nav--glass {
  background: rgba(250,250,249,0.65);  /* stone-50 @ 65% */
  border-bottom-color: rgba(0,0,0,0.08);
}

nav.nav--light-surface {
  background: rgba(250,250,249,0.45);  /* stone-50 @ 45% */
}

nav.nav--light-surface .nav-logo {
  filter: brightness(0) saturate(0);
}

nav.nav--light-surface .exp-tabs {
  background: rgba(0,0,0,0.06);
  border-color: rgba(0,0,0,0.10);
}

nav.nav--light-surface .exp-tab {
  color: rgba(0,0,0,0.45);
}

nav.nav--light-surface .exp-tab.active {
  background: rgba(0,0,0,0.08);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  color: rgba(0,0,0,0.85);
}

nav.nav--light-surface .exp-tab:hover:not(.active) {
  color: rgba(0,0,0,0.65);
  background: rgba(0,0,0,0.04);
}

.nav-logo { height: 40px; width: auto; display: block; opacity: 0.9; transition: filter 0.3s ease; }

/* ── Expandable icon tabs ── */
.exp-tabs {
  display: flex;
  align-items: center;
  gap: 3px;
  background: var(--seg-bg);
  border: 1px solid var(--seg-border);
  border-radius: var(--radius-lg);
  padding: 4px;
}

.exp-tab {
  display: flex;
  align-items: center;
  gap: 0;
  padding: 7px 8px;
  border-radius: var(--radius-md);
  border: none;
  background: transparent;
  color: var(--seg-text);
  cursor: pointer;
  font-family: var(--font-sans);
  font-size: var(--body-sm);
  font-weight: 500;
  letter-spacing: -0.01em;
  white-space: nowrap;
  overflow: hidden;
  transition:
    color 0.25s ease,
    background 0.25s ease,
    padding 0.35s var(--ease-spring);
}

.exp-tab .tab-label {
  opacity: 1;
}

/* Nav tabs: labels always visible, no icon expand behavior */
.nav-tabs .exp-tab {
  padding: 7px 14px;
}

.exp-tab.active {
  background: var(--seg-active-bg);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  color: var(--seg-active-text);
  padding: 7px 14px;
}

.exp-tab:hover:not(.active) {
  color: var(--seg-hover-text);
  background: var(--seg-hover-bg);
}

.exp-tab:focus-visible { outline: 2px solid var(--brand-gold); outline-offset: 2px; border-radius: var(--radius-md); }
.exp-tab:active { opacity: 0.70; }


/* ── Theme toggle polish ── */
.theme-toggle .exp-tab {
  gap: var(--space-3);
}

/* Icons-only on smaller screens */
@media (max-width: 900px) {
  .theme-toggle .tab-label {
    display: none;
  }
}


/* ── Language switcher ── */
.lang-switcher {
  position: relative;
}

.lang-btn {
  display: flex;
  align-items: center;
  gap: 6px;
  padding: 7px 10px;
  border-radius: var(--radius-md);
  border: 1px solid var(--seg-border);
  background: var(--seg-bg);
  color: var(--seg-text);
  cursor: pointer;
  font-family: var(--font-sans);
  font-size: var(--body-sm);
  font-weight: 500;
  letter-spacing: 0.02em;
  white-space: nowrap;
  transition:
    color 0.25s ease,
    background 0.25s ease,
    border-color 0.25s ease;
}

.lang-btn:hover {
  color: var(--seg-hover-text);
  background: var(--seg-hover-bg);
}

.lang-btn:focus-visible {
  outline: 2px solid var(--brand-gold);
  outline-offset: 2px;
  border-radius: var(--radius-md);
}

.lang-chevron {
  transition: transform 0.25s var(--ease-spring);
}

.lang-btn[aria-expanded="true"] .lang-chevron {
  transform: rotate(180deg);
}

.lang-dropdown {
  position: absolute;
  top: calc(100% + 6px);
  right: 0;
  min-width: 160px;
  padding: 4px;
  margin: 0;
  list-style: none;
  background: var(--seg-bg);
  border: 1px solid var(--seg-border);
  border-radius: var(--radius-md);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  box-shadow: 0 8px 24px rgba(0,0,0,0.25);
  opacity: 0;
  visibility: hidden;
  transform: translateY(-4px);
  transition:
    opacity 0.2s ease,
    visibility 0.2s ease,
    transform 0.2s var(--ease-spring);
  z-index: 210;
}

.lang-dropdown.is-open {
  opacity: 1;
  visibility: visible;
  transform: translateY(0);
}

.lang-option {
  padding: 8px 12px;
  border-radius: var(--radius-sm);
  cursor: pointer;
  font-family: var(--font-sans);
  font-size: var(--body-sm);
  font-weight: 500;
  color: var(--seg-text);
  transition:
    color 0.15s ease,
    background 0.15s ease;
}

.lang-option:hover {
  color: var(--seg-hover-text);
  background: var(--seg-hover-bg);
}

.lang-option.active {
  color: var(--seg-active-text);
  background: var(--seg-active-bg);
}

/* Surface-aware lang switcher colors */
nav.nav--dark-surface .lang-btn {
  background: rgba(255,255,255,0.06);
  border-color: rgba(255,255,255,0.10);
  color: rgba(255,255,255,0.50);
}
nav.nav--dark-surface .lang-btn:hover {
  color: rgba(255,255,255,0.80);
  background: rgba(255,255,255,0.08);
}
nav.nav--dark-surface .lang-dropdown {
  background: rgba(20,20,24,0.92);
  border-color: rgba(255,255,255,0.10);
}
nav.nav--dark-surface .lang-option {
  color: rgba(255,255,255,0.60);
}
nav.nav--dark-surface .lang-option:hover {
  color: rgba(255,255,255,0.90);
  background: rgba(255,255,255,0.06);
}
nav.nav--dark-surface .lang-option.active {
  color: rgba(255,255,255,0.95);
  background: rgba(255,255,255,0.11);
}

nav.nav--light-surface .lang-btn {
  background: rgba(0,0,0,0.06);
  border-color: rgba(0,0,0,0.10);
  color: rgba(0,0,0,0.45);
}
nav.nav--light-surface .lang-btn:hover {
  color: rgba(0,0,0,0.65);
  background: rgba(0,0,0,0.08);
}
nav.nav--light-surface .lang-dropdown {
  background: rgba(250,250,249,0.92);
  border-color: rgba(0,0,0,0.10);
}
nav.nav--light-surface .lang-option {
  color: rgba(0,0,0,0.50);
}
nav.nav--light-surface .lang-option:hover {
  color: rgba(0,0,0,0.70);
  background: rgba(0,0,0,0.05);
}
nav.nav--light-surface .lang-option.active {
  color: rgba(0,0,0,0.85);
  background: rgba(0,0,0,0.08);
}


/* ── Burger button (mobile only) ── */
.burger-btn {
  display: none;
  justify-self: end;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  gap: 5px;
  width: 40px;
  height: 40px;
  padding: 8px;
  background: none;
  border: none;
  cursor: pointer;
  z-index: 210;
}

.burger-line {
  display: block;
  width: 22px;
  height: 2px;
  background: currentColor;
  border-radius: var(--radius-xs);
  transition:
    transform 0.35s var(--ease-spring),
    opacity 0.25s ease;
  transform-origin: center;
}

/* Animated X state */
.burger-btn.is-open .burger-line:nth-child(1) {
  transform: translateY(7px) rotate(45deg);
}
.burger-btn.is-open .burger-line:nth-child(2) {
  opacity: 0;
}
.burger-btn.is-open .burger-line:nth-child(3) {
  transform: translateY(-7px) rotate(-45deg);
}

/* Dark surface burger color */
nav.nav--dark-surface .burger-btn {
  color: rgba(255,255,255,0.85);
}
nav.nav--light-surface .burger-btn {
  color: rgba(0,0,0,0.75);
}


/* ── Mobile menu overlay ── */
.mobile-menu-overlay {
  position: fixed;
  inset: 0;
  z-index: 199;
  display: flex;
  align-items: center;
  justify-content: center;
  background: rgba(9,9,11,0.92);
  backdrop-filter: blur(24px);
  -webkit-backdrop-filter: blur(24px);
  opacity: 0;
  visibility: hidden;
  transition:
    opacity 0.35s var(--ease-spring),
    visibility 0.35s;
}

.mobile-menu-overlay.is-open {
  opacity: 1;
  visibility: visible;
}

.mobile-menu-items {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: var(--space-5);
}

.mobile-menu-item {
  font-family: var(--font-display);
  font-size: clamp(28px, 6vw, 42px);
  font-weight: 700;
  letter-spacing: -0.03em;
  color: rgba(255,255,255,0.85);
  background: none;
  border: none;
  cursor: pointer;
  padding: 10px 24px;
  border-radius: var(--radius-lg);
  transition:
    color 0.2s ease,
    background 0.2s ease,
    transform 0.35s var(--ease-spring),
    opacity 0.35s var(--ease-spring);
  transform: translateY(20px);
  opacity: 0;
}

.mobile-menu-overlay.is-open .mobile-menu-item {
  transform: translateY(0);
  opacity: 1;
}

/* Staggered entrance */
.mobile-menu-overlay.is-open .mobile-menu-item:nth-child(1) { transition-delay: 0.05s; }
.mobile-menu-overlay.is-open .mobile-menu-item:nth-child(2) { transition-delay: 0.10s; }
.mobile-menu-overlay.is-open .mobile-menu-item:nth-child(3) { transition-delay: 0.15s; }

.mobile-menu-item:hover {
  color: rgba(255,255,255,1);
  background: rgba(255,255,255,0.06);
}

.mobile-menu-item:focus-visible {
  outline: 2px solid var(--brand-gold);
  outline-offset: 4px;
  border-radius: var(--radius-lg);
}

.mobile-menu-item:active { opacity: 0.70; }


/* ── Mobile responsive nav ── */
@media (max-width: 768px) {
  .nav-tabs {
    display: none;
  }

  .burger-btn {
    display: flex;
  }

  /* Re-layout nav: logo left, burger right, no center column */
  nav {
    grid-template-columns: 1fr auto auto;
    gap: var(--space-4);
  }

  .nav-right-group {
    justify-self: end;
  }

  /* Hide theme toggle on mobile, keep lang switcher */
  .theme-toggle {
    display: none;
  }
}