/*  1. NAV SHELL */
.nav {
  position: fixed;
  inset-block-start: 0;
  inset-inline: 0;
  z-index: 100;
  background-color: var(--nav-bg);
  backdrop-filter: blur(14px);
  -webkit-backdrop-filter: blur(14px);
  border-bottom: 1px solid transparent;
  transition:
    background-color var(--t-base),
    border-color var(--t-base),
    box-shadow   var(--t-base);
}

/* Scrolled state — toggled by main.js */
.nav.is-scrolled {
  background-color: var(--surface2-translucent);
  border-color: var(--border);
  box-shadow: 0 4px 20px -5px rgba(0, 0, 0, 0.05);
}


/*  2. NAV INNER — logo | links | actions */
.nav__inner {
  display: grid;
  grid-template-columns: 1fr auto 1fr;
  align-items: center;
  height: 56px;
}

/* Right-align the actions column in grid mode */
.nav__inner > .nav__actions {
  justify-self: end;
}


/*  3. LOGO (left column) */
.nav__logo {
  /* Site logo - shared styles in base.css .brand */
}


/*  4. DESKTOP LINKS (center column) */
.nav__links {
  display: flex;
  align-items: center;
  gap: 0;
}

.nav__links li {
  position: relative;
}

.nav__link {
  display: inline-block;
  padding: 0.375rem 0.5rem; /* Reduced from 0.875rem to fit 7 links */
  font-family: var(--font-sans);
  font-size: var(--text-xs);
  font-weight: 600;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--muted);
  transition: color var(--t-fast);
  text-decoration: none;
}

.nav__link:hover {
  color: var(--text-s);
}

/* Active state — short underline bar (matches reference) */
.nav__link.is-active {
  color: var(--text-s);
}

.nav__link.is-active::after {
  content: '';
  position: absolute;
  bottom: -2px;
  left: 50%;
  transform: translateX(-50%);
  width: 20px;
  height: 2px;
  background-color: var(--text-s);
  border-radius: 2px;
}


/*  5. ACTIONS (right column — theme toggle) */
.nav__actions {
  display: flex;
  align-items: center;
  gap: 0.375rem;
}

/* Theme toggle */
.nav__theme-toggle {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 32px;
  height: 32px;
  border-radius: var(--radius-sm);
  color: var(--muted);
  transition:
    color            var(--t-fast),
    background-color var(--t-fast);
}

.nav__theme-toggle:hover {
  color: var(--text-s);
  background-color: var(--surface2);
}

/* Icon visibility per mode */
html:not(.dark) .icon--moon { display: block; }
html:not(.dark) .icon--sun  { display: none;  }
html.dark       .icon--sun  { display: block; }
html.dark       .icon--moon { display: none;  }


/*  6. BURGER BUTTON (mobile only) */
.nav__burger {
  display: none;
  flex-direction: column;
  justify-content: center;
  align-items: flex-end;
  gap: 5px;
  width: 36px;
  height: 36px;
  padding: 0.5rem;
  border-radius: var(--radius-sm);
  transition: background-color var(--t-fast);
}

.nav__burger:hover {
  background-color: var(--surface2);
}

.nav__burger-bar {
  display: block;
  height: 1.5px;
  background-color: var(--text-s);
  border-radius: 2px;
  transition:
    transform var(--t-base),
    opacity   var(--t-base),
    width     var(--t-base);
}

.nav__burger-bar:first-child { width: 18px; }
.nav__burger-bar:last-child  { width: 12px; }

.nav__burger[aria-expanded="true"] .nav__burger-bar:first-child {
  width: 18px;
  transform: translateY(3.25px) rotate(45deg);
}
.nav__burger[aria-expanded="true"] .nav__burger-bar:last-child {
  width: 18px;
  transform: translateY(-3.25px) rotate(-45deg);
}


/*  7. MOBILE MENU PANEL */
.nav__mobile {
  overflow: hidden;
  max-height: 0;
  border-top: 1px solid transparent;
  transition:
    max-height    var(--t-base),
    border-color  var(--t-base);
}

.nav__mobile.is-open {
  max-height: 500px; /* Increased from 300px to accommodate all 7 links */
  border-color: var(--border);
}

.nav__mobile-links {
  display: flex;
  flex-direction: column;
  padding: 0.75rem var(--gutter) 1.25rem;
  gap: 0.125rem;
}

.nav__mobile-link {
  display: block;
  padding: 0.625rem 0.75rem;
  font-family: var(--font-sans);
  font-size: var(--text-base);
  font-weight: 400;
  color: var(--muted);
  border-radius: var(--radius-sm);
  transition:
    color            var(--t-fast),
    background-color var(--t-fast);
}

.nav__mobile-link:hover,
.nav__mobile-link.is-active {
  color: var(--text-s);
  background-color: var(--surface2);
}


/*  8. RESPONSIVE */

/* Tighter spacing for desktop links on medium screens */
@media (max-width: 1024px) and (min-width: 821px) {
  .nav__link {
    padding-inline: 0.35rem;
    font-size: 10px;
  }
}

@media (max-width: 820px) {
  /* Collapse to flex: logo left, actions right — no ghost center column */
  .nav__inner {
    display: flex;
    justify-content: space-between;
    align-items: center;
  }

  .nav__links  { display: none; }
  .nav__burger { display: flex; }
}