/* Header Layout */
.site-header {
  background-color: var(--color-white);
  border-bottom: 1px solid var(--color-gray-200);
  position: sticky;
  top: 0;
  z-index: 100;
  box-shadow: var(--shadow-sm);
}

.header-container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 80px;
  gap: var(--space-4);
}

/* Logo */
.logo {
  display: flex;
  align-items: center;
  font-family: 'Nunito', var(--font-family-base);
  font-size: var(--font-size-xl);
  font-weight: 700;
  text-decoration: none;
  transition: transform var(--transition-fast);
}

.logo:hover {
  transform: scale(1.02);
}

.logo__text {
  background: linear-gradient(135deg, var(--color-primary) 0%, var(--color-accent) 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

/* Navigation */
.main-nav {
  display: flex;
  align-items: center;
}

.nav-list {
  display: flex;
  align-items: center;
  gap: var(--space-6);
  list-style: none;
  margin: 0;
  padding: 0;
}

.nav-list a {
  display: block;
  padding: var(--space-2) 0;
  color: var(--color-gray-700);
  font-weight: 600;
  font-size: var(--font-size-base);
  text-decoration: none;
  position: relative;
  transition: color var(--transition-fast);
}

.nav-list a::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 0;
  width: 0;
  height: 3px;
  background-color: var(--color-accent);
  border-radius: var(--radius-full);
  transition: width var(--transition-base);
}

.nav-list a:hover {
  color: var(--color-gray-900);
}

.nav-list a:hover::after {
  width: 100%;
}

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

.icon-btn {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 44px;
  height: 44px;
  border-radius: var(--radius-full);
  background-color: var(--color-secondary);
  color: var(--color-gray-800);
  text-decoration: none;
  transition: all var(--transition-fast);
}

.icon-btn:hover {
  background-color: var(--color-secondary-dark);
  transform: translateY(-2px);
  box-shadow: var(--shadow-md);
}

.icon-btn:focus-visible {
  outline: var(--focus-ring-width) solid var(--focus-ring-color);
  outline-offset: var(--focus-ring-offset);
}

/* Mobile Menu Toggle */
.mobile-menu-toggle {
  display: none;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  width: 48px;
  height: 48px;
  padding: var(--space-3);
  background: transparent;
  border: none;
  cursor: pointer;
  border-radius: var(--radius-md);
  transition: background-color var(--transition-fast);
}

.mobile-menu-toggle:hover {
  background-color: var(--color-gray-100);
}

.mobile-menu-toggle:focus-visible {
  outline: var(--focus-ring-width) solid var(--focus-ring-color);
  outline-offset: var(--focus-ring-offset);
}

.hamburger {
  display: block;
  width: 24px;
  height: 2px;
  background-color: var(--color-gray-800);
  position: relative;
  transition: background-color var(--transition-fast);
}

.hamburger::before,
.hamburger::after {
  content: '';
  position: absolute;
  left: 0;
  width: 100%;
  height: 2px;
  background-color: var(--color-gray-800);
  transition: transform var(--transition-base);
}

.hamburger::before {
  top: -8px;
}

.hamburger::after {
  top: 8px;
}

/* Mobile Menu Open State */
.mobile-menu-toggle[aria-expanded="true"] .hamburger {
  background-color: transparent;
}

.mobile-menu-toggle[aria-expanded="true"] .hamburger::before {
  transform: translateY(8px) rotate(45deg);
}

.mobile-menu-toggle[aria-expanded="true"] .hamburger::after {
  transform: translateY(-8px) rotate(-45deg);
}

/* Responsive */
@media (max-width: 768px) {
  .mobile-menu-toggle {
    display: flex;
    order: 3;
  }
  
  .main-nav {
    position: fixed;
    top: 80px;
    left: 0;
    right: 0;
    bottom: 0;
    background-color: var(--color-white);
    padding: var(--space-6);
    transform: translateX(100%);
    transition: transform var(--transition-base);
    overflow-y: auto;
    box-shadow: var(--shadow-lg);
  }
  
  .main-nav.is-open {
    transform: translateX(0);
  }
  
  .nav-list {
    flex-direction: column;
    align-items: flex-start;
    gap: var(--space-4);
  }
  
  .nav-list a {
    font-size: var(--font-size-lg);
    padding: var(--space-3) 0;
    width: 100%;
  }
  
  .nav-list a::after {
    display: none;
  }
  
  .header-actions {
    margin-left: auto;
    margin-right: var(--space-3);
  }
}

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