/* ==========================================================================
   Header Styles - Modern, Accessible, Mobile-First
   ========================================================================== */

.site-header {
  position: sticky;
  top: 0;
  width: 100%;
  background-color: var(--color-white);
  box-shadow: var(--shadow-md);
  z-index: var(--z-sticky);
  transition: all var(--transition-base);
}

.site-header.scrolled {
  box-shadow: var(--shadow-lg);
}

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

/* Logo */
.site-logo {
  flex-shrink: 0;
}

.site-logo img {
  height: auto;
  max-height: 50px;
  width: auto;
  max-width: 180px;
  display: block;
}

@media (min-width: 768px) {
  .site-logo img {
    max-height: 60px;
    max-width: 220px;
  }
}

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

@media (min-width: 1024px) {
  .main-nav {
    display: flex;
    align-items: center;
    gap: var(--space-2);
  }
}

.nav-list {
  display: flex;
  align-items: center;
  gap: var(--space-1);
  list-style: none;
  margin: 0;
  padding: 0;
}

.nav-item {
  position: relative;
}

.nav-link {
  display: flex;
  align-items: center;
  gap: var(--space-1);
  padding: var(--space-2) var(--space-3);
  font-size: var(--text-base);
  font-weight: var(--font-medium);
  color: var(--color-dark);
  text-decoration: none;
  border-radius: var(--radius-md);
  transition: all var(--transition-fast);
  min-height: 44px; /* WCAG */
}

.nav-link:hover,
.nav-link:focus-visible {
  color: var(--color-primary);
  background-color: var(--color-gray-100);
}

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

/* Dropdown */
.has-dropdown > .nav-link::after {
  content: '';
  width: 0;
  height: 0;
  border-left: 4px solid transparent;
  border-right: 4px solid transparent;
  border-top: 5px solid currentColor;
  margin-left: var(--space-1);
}

.dropdown-menu {
  position: absolute;
  top: 100%;
  left: 0;
  min-width: 240px;
  padding: var(--space-2);
  background-color: var(--color-white);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-xl);
  opacity: 0;
  visibility: hidden;
  transform: translateY(-10px);
  transition: all var(--transition-base);
  list-style: none;
  margin: 0;
  z-index: var(--z-dropdown);
}

.has-dropdown:hover .dropdown-menu,
.has-dropdown:focus-within .dropdown-menu {
  opacity: 1;
  visibility: visible;
  transform: translateY(0);
}

.dropdown-menu .nav-link {
  width: 100%;
  justify-content: flex-start;
}

/* Header Actions */
.header-actions {
  display: flex;
  align-items: center;
  gap: var(--space-3);
}

.header-phone {
  display: none;
}

@media (min-width: 768px) {
  .header-phone {
    display: inline-flex;
    align-items: center;
    gap: var(--space-2);
    padding: var(--space-2) var(--space-4);
    font-weight: var(--font-semibold);
    color: var(--color-dark);
    text-decoration: none;
    border: 2px solid var(--color-gray-300);
    border-radius: var(--radius-md);
    transition: all var(--transition-fast);
    min-height: 44px;
  }
  
  .header-phone:hover {
    color: var(--color-primary);
    border-color: var(--color-primary);
  }
}

.header-book-btn {
  display: none;
}

@media (min-width: 1024px) {
  .header-book-btn {
    display: inline-flex;
  }
}

/* Mobile Menu Toggle */
.mobile-menu-toggle {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 44px;
  height: 44px;
  padding: 0;
  background: none;
  border: 2px solid var(--color-gray-300);
  border-radius: var(--radius-md);
  cursor: pointer;
  transition: all var(--transition-fast);
}

.mobile-menu-toggle:hover,
.mobile-menu-toggle:focus-visible {
  border-color: var(--color-primary);
  background-color: var(--color-gray-100);
}

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

@media (min-width: 1024px) {
  .mobile-menu-toggle {
    display: none;
  }
}

.hamburger {
  width: 24px;
  height: 18px;
  position: relative;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
}

.hamburger span {
  display: block;
  width: 100%;
  height: 2px;
  background-color: var(--color-dark);
  transition: all var(--transition-fast);
}

.mobile-menu-toggle.active .hamburger span:nth-child(1) {
  transform: translateY(8px) rotate(45deg);
}

.mobile-menu-toggle.active .hamburger span:nth-child(2) {
  opacity: 0;
}

.mobile-menu-toggle.active .hamburger span:nth-child(3) {
  transform: translateY(-8px) rotate(-45deg);
}

/* Mobile Menu */
.mobile-menu {
  position: fixed;
  top: 0;
  right: -100%;
  width: 100%;
  max-width: 400px;
  height: 100vh;
  background-color: var(--color-white);
  box-shadow: var(--shadow-2xl);
  overflow-y: auto;
  transition: right var(--transition-base);
  z-index: var(--z-modal);
  padding: var(--space-6);
}

.mobile-menu.active {
  right: 0;
}

@media (min-width: 1024px) {
  .mobile-menu {
    display: none;
  }
}

.mobile-menu-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: var(--space-6);
  padding-bottom: var(--space-4);
  border-bottom: 1px solid var(--color-gray-300);
}

.mobile-menu-close {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 44px;
  height: 44px;
  background: none;
  border: none;
  font-size: var(--text-2xl);
  cursor: pointer;
  color: var(--color-dark);
}

.mobile-nav-list {
  list-style: none;
  margin: 0;
  padding: 0;
}

.mobile-nav-item {
  border-bottom: 1px solid var(--color-gray-300);
}

.mobile-nav-link {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: var(--space-4) 0;
  font-size: var(--text-lg);
  font-weight: var(--font-medium);
  color: var(--color-dark);
  text-decoration: none;
  min-height: 44px;
}

.mobile-nav-link:hover {
  color: var(--color-primary);
}

.mobile-dropdown-toggle {
  width: 44px;
  height: 44px;
  display: flex;
  align-items: center;
  justify-content: center;
  background: none;
  border: none;
  cursor: pointer;
  color: var(--color-dark);
}

.mobile-submenu {
  max-height: 0;
  overflow: hidden;
  transition: max-height var(--transition-base);
  list-style: none;
  margin: 0;
  padding: 0;
}

.mobile-submenu.active {
  max-height: 1000px;
}

.mobile-submenu .mobile-nav-link {
  padding-left: var(--space-4);
  font-size: var(--text-base);
}

.mobile-menu-actions {
  margin-top: var(--space-8);
  padding-top: var(--space-6);
  border-top: 1px solid var(--color-gray-300);
}

.mobile-menu-actions .btn {
  width: 100%;
  margin-bottom: var(--space-3);
}

/* Mobile Menu Backdrop */
.mobile-menu-backdrop {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background-color: rgba(0, 0, 0, 0.5);
  opacity: 0;
  visibility: hidden;
  transition: all var(--transition-base);
  z-index: var(--z-modal-backdrop);
}

.mobile-menu-backdrop.active {
  opacity: 1;
  visibility: visible;
}

@media (min-width: 1024px) {
  .mobile-menu-backdrop {
    display: none;
  }
}