/* Header */
.site-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0 var(--space-md);
  background: var(--color-secondary);
  position: sticky;
  top: 0;
  z-index: 100;
  box-shadow: var(--shadow-md);
}

.logo {
  display: flex;
  align-items: center;
  gap: var(--space-sm);
}

.logo img {
  height: 36px;
  width: auto;
}

.logo-text {
  color: white;
  font-size: var(--font-size-lg);
  font-weight: 700;
}

.logo-text span {
  color: var(--color-primary);
}

/* Hamburger */
.nav-toggle {
  display: flex;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  width: 44px;
  height: 44px;
  padding: 0;
  z-index: 110;
}

.nav-toggle-icon,
.nav-toggle-icon::before,
.nav-toggle-icon::after {
  display: block;
  width: 24px;
  height: 2px;
  background: white;
  border-radius: 2px;
  transition: var(--transition-base);
}

.nav-toggle-icon {
  position: relative;
}

.nav-toggle-icon::before,
.nav-toggle-icon::after {
  content: '';
  position: absolute;
  left: 0;
}

.nav-toggle-icon::before { top: -7px; }
.nav-toggle-icon::after { top: 7px; }

/* Hamburger active state */
.nav-toggle[aria-expanded="true"] .nav-toggle-icon {
  background: transparent;
}

.nav-toggle[aria-expanded="true"] .nav-toggle-icon::before {
  top: 0;
  transform: rotate(45deg);
}

.nav-toggle[aria-expanded="true"] .nav-toggle-icon::after {
  top: 0;
  transform: rotate(-45deg);
}

/* Navigation sidebar */
.main-nav {
  grid-area: nav;
  position: fixed;
  top: var(--header-height);
  left: 0;
  bottom: 0;
  width: var(--sidebar-width);
  background: var(--color-bg);
  border-right: 1px solid var(--color-border);
  overflow-y: auto;
  transform: translateX(-100%);
  transition: transform var(--transition-base);
  z-index: 90;
}

.main-nav.is-open {
  transform: translateX(0);
}

/* Overlay */
.nav-overlay {
  display: none;
  position: fixed;
  inset: 0;
  top: var(--header-height);
  background: rgba(0,0,0,0.4);
  z-index: 80;
}

.nav-overlay.is-visible {
  display: block;
}

/* Nav list */
.nav-list {
  padding: var(--space-sm) 0;
}

.nav-item {}

.nav-link {
  display: flex;
  align-items: center;
  gap: var(--space-sm);
  padding: var(--space-sm) var(--space-lg);
  color: var(--color-text);
  font-size: var(--font-size-sm);
  font-weight: 400;
  transition: background var(--transition-fast), color var(--transition-fast);
  border-left: 3px solid transparent;
}

.nav-link:hover,
.nav-link:focus-visible {
  background: var(--color-bg-alt);
  color: var(--color-primary);
}

.nav-link.is-active {
  color: var(--color-primary);
  font-weight: 600;
  border-left-color: var(--color-primary);
  background: rgba(244, 108, 32, 0.05);
}

.nav-link svg {
  width: 18px;
  height: 18px;
  flex-shrink: 0;
  opacity: 0.6;
}

/* Nav divider */
.nav-divider {
  height: 1px;
  background: var(--color-border-light);
  margin: var(--space-sm) var(--space-lg);
}

/* Nav section label */
.nav-section-label {
  padding: var(--space-md) var(--space-lg) var(--space-xs);
  font-size: var(--font-size-xs);
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: var(--color-text-muted);
}

/* Sub-nav (collapsible) */
.nav-submenu {
  overflow: hidden;
  max-height: 0;
  transition: max-height var(--transition-base);
}

.nav-submenu.is-open {
  max-height: 200px;
}

.nav-submenu .nav-link {
  padding-left: var(--space-2xl);
  font-size: var(--font-size-xs);
}

.nav-toggle-sub {
  display: flex;
  align-items: center;
  justify-content: space-between;
  width: 100%;
  padding: var(--space-sm) var(--space-lg);
  color: var(--color-text);
  font-size: var(--font-size-sm);
  text-align: left;
  border-left: 3px solid transparent;
  transition: background var(--transition-fast);
}

.nav-toggle-sub:hover {
  background: var(--color-bg-alt);
}

.nav-toggle-sub .chevron {
  width: 16px;
  height: 16px;
  transition: transform var(--transition-fast);
}

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

/* Language switcher */
.lang-switcher {
  display: flex;
  gap: var(--space-xs);
  padding: var(--space-sm) var(--space-lg);
}

.lang-btn {
  padding: var(--space-xs) var(--space-sm);
  border-radius: var(--border-radius-sm);
  font-size: var(--font-size-sm);
  font-weight: 600;
  color: var(--color-text-light);
  transition: all var(--transition-fast);
}

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

.lang-btn.is-active {
  background: var(--color-primary);
  color: white;
}

/* Desktop: sidebar always visible */
@media (min-width: 1024px) {
  .nav-toggle {
    display: none;
  }

  .main-nav {
    position: static;
    transform: none;
    border-right: 1px solid var(--color-border);
    min-height: calc(100vh - var(--header-height));
  }

  .nav-overlay {
    display: none !important;
  }
}