/* ============================================
   HEADER.CSS - Site Header & Navigation
   ============================================ */

/* Skip Link */
.skip-link {
  position: absolute;
  top: -40px;
  left: 0;
  background: var(--color-primary);
  color: white;
  padding: var(--space-2) var(--space-4);
  z-index: 100;
  text-decoration: none;
  font-weight: 600;
  border-radius: 0 0 var(--radius-md) 0;
  transition: top var(--transition-fast);
}

.skip-link:focus {
  top: 0;
}

/* Header Layout */
.site-header {
  position: sticky;
  top: 0;
  z-index: 50;
  background-color: var(--color-bg);
  border-bottom: 1px solid var(--gray-200);
  box-shadow: var(--shadow-sm);
}

.header-container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: var(--header-height);
  gap: var(--space-4);
}

/* Logo */
.logo {
  display: flex;
  align-items: center;
  text-decoration: none;
  flex-shrink: 0;
}

.logo__text {
  font-family: 'Rajdhani', sans-serif;
  font-size: var(--text-2xl);
  font-weight: 700;
  color: var(--color-primary);
  letter-spacing: 0.02em;
  line-height: 1;
}

/* Desktop Navigation */
.main-nav {
  display: none;
}

.nav-list {
  display: flex;
  align-items: center;
  gap: var(--space-2);
}

.nav-link {
  display: block;
  padding: var(--space-2) var(--space-3);
  color: var(--color-text);
  font-weight: 500;
  font-size: var(--text-sm);
  border-radius: var(--radius-md);
  transition: color var(--transition-fast), background-color var(--transition-fast);
  position: relative;
}

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

.nav-link:focus-visible {
  outline: 2px solid var(--color-primary);
  outline-offset: 2px;
}

/* Header Actions */
.header-actions {
  display: flex;
  align-items: center;
  gap: var(--space-2);
  margin-left: auto;
}

.header-icon-link {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 2.5rem;
  height: 2.5rem;
  color: var(--color-text-heading);
  border-radius: var(--radius-md);
  transition: color var(--transition-fast), background-color var(--transition-fast);
}

.header-icon-link:hover,
.header-icon-link:focus-visible {
  color: var(--color-primary);
  background-color: var(--color-bg-secondary);
}

.header-icon-link:focus-visible {
  outline: 2px solid var(--color-primary);
  outline-offset: 2px;
}

/* Mobile Menu Toggle */
.mobile-menu-toggle {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 2.5rem;
  height: 2.5rem;
  color: var(--color-text-heading);
  border-radius: var(--radius-md);
  font-size: var(--text-lg);
  transition: color var(--transition-fast), background-color var(--transition-fast);
}

.mobile-menu-toggle:hover,
.mobile-menu-toggle:focus-visible {
  color: var(--color-primary);
  background-color: var(--color-bg-secondary);
}

.mobile-menu-toggle[aria-expanded="true"] {
  color: var(--color-primary);
}

/* Mobile Navigation */
.mobile-nav {
  position: fixed;
  top: 0;
  right: 0;
  width: 100%;
  max-width: 320px;
  height: 100vh;
  background-color: var(--color-bg);
  z-index: 100;
  transform: translateX(100%);
  transition: transform var(--transition-slow), visibility var(--transition-slow);
  visibility: hidden;
  display: flex;
  flex-direction: column;
  box-shadow: var(--shadow-xl);
}

.mobile-nav[hidden] {
  display: none;
}

.mobile-nav:not([hidden]) {
  transform: translateX(0);
  visibility: visible;
}

.mobile-nav__header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: var(--space-4);
  border-bottom: 1px solid var(--gray-200);
}

.mobile-menu-close {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 2.5rem;
  height: 2.5rem;
  color: var(--color-text-heading);
  border-radius: var(--radius-md);
  font-size: var(--text-xl);
  transition: color var(--transition-fast), background-color var(--transition-fast);
}

.mobile-menu-close:hover,
.mobile-menu-close:focus-visible {
  color: var(--color-danger);
  background-color: var(--color-danger-subtle);
}

.mobile-nav__list {
  padding: var(--space-4);
  display: flex;
  flex-direction: column;
  gap: var(--space-1);
  overflow-y: auto;
}

.mobile-nav__link {
  display: block;
  padding: var(--space-3) var(--space-4);
  color: var(--color-text-heading);
  font-weight: 600;
  font-size: var(--text-lg);
  border-radius: var(--radius-md);
  transition: color var(--transition-fast), background-color var(--transition-fast);
}

.mobile-nav__link:hover,
.mobile-nav__link:focus-visible {
  color: var(--color-primary);
  background-color: var(--color-bg-secondary);
}

.mobile-nav__link:focus-visible {
  outline: 2px solid var(--color-primary);
  outline-offset: 2px;
}

.mobile-overlay {
  position: fixed;
  inset: 0;
  background-color: rgba(15, 23, 42, 0.5);
  z-index: 99;
  opacity: 0;
  transition: opacity var(--transition-slow);
}

.mobile-overlay[hidden] {
  display: none;
}

.mobile-overlay:not([hidden]) {
  opacity: 1;
}

/* Utilities */
.visually-hidden {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border-width: 0;
}

/* Responsive */
@media (min-width: 768px) {
  .main-nav {
    display: block;
    margin-left: auto;
  }
  
  .mobile-menu-toggle {
    display: none;
  }
  
  .header-actions {
    margin-left: var(--space-6);
  }
}

@media (prefers-reduced-motion: reduce) {
  .mobile-nav,
  .mobile-overlay {
    transition: none;
  }
}