/* ==========================================================================
   NAV.CSS — Header Navigation, Brand Logo, Theme Switcher & Mobile Menu
   Max lines: < 250 lines
   ========================================================================== */

.nav {
  position: sticky;
  top: 0;
  z-index: 1000;
  background: var(--color-bg-primary);
  border-bottom: 1px solid var(--color-border);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  transition: all var(--transition-base);
}

.nav.scrolled {
  box-shadow: 0 4px 20px rgba(0, 0, 0, 0.12);
}

.nav__container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 72px;
}

/* Brand Logo */
.nav__logo {
  display: inline-flex;
  align-items: center;
  gap: var(--sp-3);
  text-decoration: none;
  transition: opacity var(--transition-fast);
}

.nav__logo:hover {
  opacity: 0.88;
}

.nav__logo-img {
  height: 34px;
  width: auto;
  max-width: 155px;
  display: block;
  object-fit: contain;
}

.nav__logo-img--light {
  display: none;
}
.nav__logo-img--dark {
  display: block;
}

[data-theme="light"] .nav .nav__logo-img--dark {
  display: none;
}
[data-theme="light"] .nav .nav__logo-img--light {
  display: block;
}

/* Links */
.nav__links {
  display: flex;
  align-items: center;
  gap: var(--sp-6);
}

.nav__link {
  font-size: var(--text-sm);
  font-weight: 500;
  color: var(--color-text-secondary);
  transition: color var(--transition-fast);
  padding: 0.5rem 0;
  position: relative;
}

.nav__link:hover,
.nav__link[aria-current="page"] {
  color: var(--color-text-primary);
}

.nav__link[aria-current="page"]::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 0;
  width: 100%;
  height: 2px;
  background-color: var(--color-accent);
  border-radius: var(--radius-full);
}

/* Actions Group */
.nav__actions {
  display: flex;
  align-items: center;
  gap: var(--sp-3);
}

/* Mobile Toggle Hamburger */
.nav__toggle {
  display: none;
  width: 40px;
  height: 40px;
  border-radius: var(--radius-md);
  border: 1px solid var(--color-border);
  background: var(--color-bg-glass);
  align-items: center;
  justify-content: center;
  flex-direction: column;
  gap: 5px;
  cursor: pointer;
}

.nav__toggle-bar {
  width: 20px;
  height: 2px;
  background: var(--color-text-primary);
  border-radius: 2px;
  transition: transform var(--transition-base), opacity var(--transition-base);
}

.nav--open .nav__toggle-bar:nth-child(1) {
  transform: translateY(7px) rotate(45deg);
}

.nav--open .nav__toggle-bar:nth-child(2) {
  opacity: 0;
}

.nav--open .nav__toggle-bar:nth-child(3) {
  transform: translateY(-7px) rotate(-45deg);
}

/* Mobile Drawer Menu */
.nav__mobile-menu {
  display: none;
  position: fixed;
  top: 72px;
  left: 0;
  right: 0;
  bottom: 0;
  background: var(--color-bg-primary);
  padding: var(--sp-6) var(--sp-4);
  flex-direction: column;
  gap: var(--sp-4);
  z-index: 999;
  border-top: 1px solid var(--color-border);
  overflow-y: auto;
}

.nav__mobile-menu.open {
  display: flex;
}

.nav__mobile-link {
  font-size: var(--text-lg);
  font-weight: 600;
  color: var(--color-text-primary);
  padding: var(--sp-3) var(--sp-2);
  border-radius: var(--radius-md);
  transition: background-color var(--transition-fast);
}

.nav__mobile-link:hover {
  background: var(--color-bg-surface);
  color: var(--color-accent);
}

.nav__mobile-cta {
  margin-top: auto;
  display: flex;
  flex-direction: column;
  gap: var(--sp-3);
  padding-top: var(--sp-4);
}