/* ============================================
   布局和导航栏样式
   ============================================ */

@import url('global.css');

/* ===== 固定导航栏 ===== */
header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  background: rgba(15, 20, 24, 0.92);
  border-bottom: 1px solid rgba(255, 255, 255, 0.08);
  box-shadow: 0 10px 30px rgba(0, 0, 0, 0.65);
  backdrop-filter: blur(12px);
  z-index: var(--z-fixed);
  transition: all var(--transition-base);
}

header.scrolled {
  background: rgba(9, 12, 14, 0.98);
}

.navbar {
  display: flex;
  align-items: center;
  justify-content: flex-start;
  gap: var(--spacing-xl);
  padding: var(--spacing-md) var(--spacing-xl) var(--spacing-md) 0;
  max-width: var(--container-max-width);
  margin: 0 auto;
  width: 100%;
}

.navbar-brand {
  display: flex;
  align-items: center;
  gap: var(--spacing-sm);
  text-decoration: none;
  font-size: var(--font-size-xl);
  font-weight: var(--font-weight-bold);
  color: var(--color-text);
  max-width: clamp(180px, 28vw, 380px);
  flex: 0 1 clamp(180px, 28vw, 380px);
}

.navbar-brand .brand-icon {
  font-size: var(--font-size-2xl);
  display: inline-flex;
  align-items: center;
}

.navbar-brand .brand-name {
  color: var(--color-accent);
  line-height: 1.2;
  font-size: var(--font-size-lg);
  font-weight: var(--font-weight-bold);
  white-space: nowrap;
}

@media (max-width: 1200px) {
  .navbar-brand {
    max-width: 360px;
  }

  .navbar-brand .brand-name {
    font-size: var(--font-size-base);
  }
}

@media (max-width: 768px) {
  .navbar-brand {
    max-width: 260px;
  }

  .navbar-brand .brand-name {
    font-size: var(--font-size-sm);
  }
}

/* ===== 导航菜单 ===== */
.navbar-menu {
  display: flex;
  list-style: none;
  gap: var(--spacing-sm);
  align-items: center;
  flex-wrap: nowrap;
  margin-left: auto;
  margin-top: var(--spacing-xs);
}

.navbar-item {
  position: relative;
}

.navbar-link {
  display: block;
  padding: var(--spacing-md) var(--spacing-md);
  color: rgba(236, 239, 241, 0.7);
  text-decoration: none;
  font-weight: var(--font-weight-medium);
  transition: all var(--transition-base);
  border-bottom: 2px solid transparent;
  font-size: calc(var(--font-size-base) - 2px);
  white-space: nowrap;
}

.navbar-link:hover {
  color: var(--color-primary);
  border-bottom-color: var(--color-accent);
}

.navbar-link.active {
  color: var(--color-primary);
  border-bottom-color: var(--color-accent);
}

/* ===== 下拉菜单 ===== */
.dropdown {
  position: relative;
}

.dropdown-toggle::after {
  content: '▼';
  font-size: 10px;
  margin-left: var(--spacing-sm);
  transition: transform var(--transition-base);
}

.dropdown:hover .dropdown-toggle::after {
  transform: rotate(180deg);
}

.dropdown-menu {
  position: absolute;
  top: 100%;
  left: 0;
  background-color: rgba(22, 28, 33, 0.98);
  min-width: 200px;
  list-style: none;
  border-radius: var(--border-radius-md);
  box-shadow: 0 20px 50px rgba(0, 0, 0, 0.55);
  border: 1px solid rgba(255, 255, 255, 0.08);
  opacity: 0;
  visibility: hidden;
  transform: translateY(-10px);
  transition: all var(--transition-base);
  z-index: var(--z-dropdown);
  margin-top: var(--spacing-sm);
}

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

.dropdown-item {
  display: block;
  padding: var(--spacing-md) var(--spacing-lg);
  color: rgba(236, 239, 241, 0.75);
  text-decoration: none;
  transition: all var(--transition-base);
  border-left: 3px solid transparent;
}

.dropdown-item:hover {
  background-color: rgba(55, 71, 79, 0.4);
  color: var(--color-primary);
  border-left-color: var(--color-primary);
  padding-left: calc(var(--spacing-lg) + 4px);
}

.dropdown-item:first-child {
  border-radius: var(--border-radius-md) var(--border-radius-md) 0 0;
}

.dropdown-item:last-child {
  border-radius: 0 0 var(--border-radius-md) var(--border-radius-md);
}

/* ===== 移动菜单按钮 ===== */
.navbar-toggle {
  display: none;
  background: none;
  border: none;
  font-size: var(--font-size-2xl);
  color: var(--color-text);
  cursor: pointer;
}

/* ===== 页面主体 ===== */
main {
  margin-top: 90px;
  min-height: calc(100vh - 90px);
}

/* ===== 页脚 ===== */
footer {
  background: linear-gradient(180deg, rgba(12, 17, 21, 0.95), rgba(8, 11, 13, 0.98));
  color: var(--color-text);
  padding: var(--spacing-3xl) var(--spacing-lg);
  margin-top: var(--spacing-5xl);
  border-top: 1px solid rgba(255, 255, 255, 0.08);
}

.footer-content {
  max-width: var(--container-max-width);
  margin: 0 auto;
}

.footer-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: var(--spacing-2xl);
  margin-bottom: var(--spacing-3xl);
}

.footer-section h3 {
  color: var(--color-accent);
  font-size: var(--font-size-lg);
  margin-bottom: var(--spacing-lg);
}

.footer-section ul {
  list-style: none;
  margin: 0;
}

.footer-section li {
  margin-bottom: var(--spacing-md);
}

.footer-section a {
  color: rgba(236, 239, 241, 0.75);
  text-decoration: none;
  transition: color var(--transition-base);
}

.footer-section a:hover {
  color: var(--color-primary);
}

.footer-bottom {
  border-top: 1px solid rgba(255, 255, 255, 0.1);
  padding-top: var(--spacing-2xl);
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.footer-copyright {
  font-size: var(--font-size-sm);
  color: rgba(255, 255, 255, 0.7);
}

.footer-social {
  display: flex;
  gap: var(--spacing-lg);
}

.social-link {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 40px;
  height: 40px;
  background-color: rgba(255, 255, 255, 0.08);
  border-radius: 50%;
  color: var(--color-text);
  text-decoration: none;
  transition: all var(--transition-base);
}

.social-link:hover {
  background-color: var(--color-primary);
  color: var(--color-secondary-dark);
}

/* ===== 面包屑导航 ===== */
.breadcrumb {
  display: flex;
  list-style: none;
  gap: var(--spacing-md);
  margin-bottom: var(--spacing-xl);
  font-size: var(--font-size-sm);
  color: var(--color-text-light);
}

.breadcrumb-item {
  color: inherit;
}

.breadcrumb-item::after {
  content: '/';
  margin-left: var(--spacing-md);
}

.breadcrumb-item:last-child::after {
  content: '';
}

.breadcrumb-item a {
  color: var(--color-text-light);
  text-transform: uppercase;
  letter-spacing: 0.08em;
}

.breadcrumb-item.active {
  color: var(--color-text);
}

/* ===== 响应式导航 ===== */
@media (max-width: 768px) {
  .navbar {
    flex-wrap: wrap;
    padding: var(--spacing-md);
  }
  
  .navbar-toggle {
    display: block;
  }
  
  .navbar-menu {
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    background-color: rgba(7, 9, 11, 0.98);
    flex-direction: column;
    gap: 0;
    max-height: 0;
    overflow: hidden;
    transition: max-height var(--transition-base);
    box-shadow: 0 20px 50px rgba(0, 0, 0, 0.6);
    margin-left: 0;
    margin-top: 0;
  }
  
  .navbar-menu.active {
    max-height: 500px;
  }
  
  .navbar-item {
    width: 100%;
  }
  
  .navbar-link {
    padding: var(--spacing-lg);
    border-bottom: 1px solid var(--color-border);
    border-right: 3px solid transparent;
  }
  
  .navbar-link:hover {
    border-bottom: 1px solid var(--color-border);
    border-right-color: var(--color-accent);
  }
  
  .dropdown-menu {
    position: static;
    opacity: 0;
    visibility: hidden;
    max-height: 0;
    overflow: hidden;
    transform: none;
    box-shadow: none;
    background-color: rgba(21, 27, 32, 0.95);
    transition: max-height var(--transition-base);
  }
  
  .dropdown.active .dropdown-menu {
    opacity: 1;
    visibility: visible;
    max-height: 500px;
  }
  
  .footer-grid {
    grid-template-columns: repeat(2, 1fr);
  }
  
  .footer-bottom {
    flex-direction: column;
    gap: var(--spacing-lg);
    text-align: center;
  }
}

@media (max-width: 480px) {
  .footer-grid {
    grid-template-columns: 1fr;
  }
  
  .navbar-brand {
    font-size: var(--font-size-lg);
  }
}