/* =====================================================
   导航栏样式表 - 固定导航栏 + 二级下拉菜单
   ===================================================== */

/* ===== 导航栏容器 ===== */
.navbar {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  background-color: var(--surface-hero);
  color: white;
  padding: var(--spacing-md) 0;
  box-shadow: var(--shadow-md);
  z-index: 1000;
  transition: all var(--transition-base);
  border-bottom: 1px solid rgba(46, 211, 255, 0.18);
}

.navbar.scrolled {
  padding: var(--spacing-sm) 0;
  box-shadow: var(--shadow-lg);
}

.navbar-container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  max-width: var(--container-xl);
  margin: 0 auto;
  padding: 0 var(--spacing-lg);
}

/* ===== 品牌/Logo ===== */
.navbar-brand {
  display: flex;
  align-items: center;
  gap: var(--spacing-md);
  font-size: var(--font-size-lg);
  font-weight: var(--font-weight-bold);
  color: white;
  text-decoration: none;
  transition: all var(--transition-base);
  white-space: nowrap;
}

.navbar-brand:hover {
  color: var(--color-accent);
}

.navbar-logo {
  width: 40px;
  height: 40px;
  background-color: var(--color-accent);
  border-radius: var(--border-radius-lg);
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: var(--font-weight-bold);
  color: var(--color-primary);
  font-size: var(--font-size-lg);
}

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

.navbar-item {
  position: relative;
}

.navbar-link {
  display: flex;
  align-items: center;
  gap: var(--spacing-sm);
  color: white;
  text-decoration: none;
  font-size: var(--font-size-sm);
  font-weight: var(--font-weight-medium);
  transition: color var(--transition-base);
  padding: var(--spacing-sm) var(--spacing-md);
  border-radius: var(--border-radius-md);
  white-space: nowrap;
}

.navbar-link:hover {
  color: var(--color-accent);
  background-color: rgba(255, 255, 255, 0.1);
}

.navbar-link.active {
  color: var(--color-accent);
  border-bottom: 2px solid var(--color-accent);
}

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

.navbar-dropdown-toggle::after {
  content: '';
  display: inline-block;
  width: 6px;
  height: 6px;
  border-right: 2px solid currentColor;
  border-bottom: 2px solid currentColor;
  transform: rotate(45deg);
  margin-left: var(--spacing-sm);
  transition: transform var(--transition-base);
}

.navbar-dropdown.open .navbar-dropdown-toggle::after {
  transform: rotate(-135deg);
}

.navbar-dropdown-menu {
  position: absolute;
  top: 100%;
  left: 0;
  background-color: white;
  border-radius: var(--border-radius-lg);
  box-shadow: var(--shadow-lg);
  min-width: 200px;
  list-style: none;
  opacity: 0;
  visibility: hidden;
  transform: translateY(-10px);
  transition: all var(--transition-base);
  margin-top: var(--spacing-md);
  overflow: hidden;
}

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

.navbar-dropdown-item {
  padding: var(--spacing-md) var(--spacing-lg);
  border-bottom: 1px solid var(--color-border);
}

.navbar-dropdown-item:last-child {
  border-bottom: none;
}

.navbar-dropdown-link {
  display: block;
  color: var(--color-text-primary);
  text-decoration: none;
  font-size: var(--font-size-base);
  font-weight: var(--font-weight-normal);
  transition: all var(--transition-base);
}

.navbar-dropdown-link:hover {
  color: var(--color-accent);
  padding-left: var(--spacing-md);
}

/* ===== 右侧操作 ===== */
.navbar-actions {
  display: flex;
  align-items: center;
  gap: var(--spacing-lg);
}

.navbar-search {
  position: relative;
  display: none;
}

.navbar-search-input {
  padding: var(--spacing-sm) var(--spacing-md);
  border: none;
  border-radius: var(--border-radius-md);
  background-color: rgba(255, 255, 255, 0.2);
  color: white;
  font-size: var(--font-size-sm);
}

.navbar-search-input::placeholder {
  color: rgba(255, 255, 255, 0.6);
}

.navbar-search-input:focus {
  outline: none;
  background-color: rgba(255, 255, 255, 0.3);
}

.navbar-cta {
  display: inline-block;
  padding: var(--spacing-sm) var(--spacing-lg);
  background-color: var(--color-accent);
  color: var(--color-primary);
  border-radius: var(--border-radius-md);
  text-decoration: none;
  font-weight: var(--font-weight-semibold);
  transition: all var(--transition-base);
  font-size: var(--font-size-sm);
}

.navbar-cta:hover {
  background-color: var(--color-accent-light);
  transform: translateY(-2px);
  box-shadow: var(--shadow-md);
}

/* ===== 移动菜单按钮 ===== */
.navbar-toggle {
  display: none;
  flex-direction: column;
  gap: 5px;
  background: none;
  border: none;
  cursor: pointer;
  padding: var(--spacing-sm);
}

.navbar-toggle span {
  width: 25px;
  height: 3px;
  background-color: white;
  border-radius: 2px;
  transition: all var(--transition-base);
}

.navbar-toggle.open span:nth-child(1) {
  transform: rotate(45deg) translate(8px, 8px);
}

.navbar-toggle.open span:nth-child(2) {
  opacity: 0;
}

.navbar-toggle.open span:nth-child(3) {
  transform: rotate(-45deg) translate(7px, -7px);
}

/* ===== 响应式设计 ===== */
@media (max-width: 1024px) {
  .navbar-menu {
    gap: var(--spacing-lg);
  }
  
  .navbar-link {
    font-size: var(--font-size-sm);
    padding: var(--spacing-sm) var(--spacing-md);
  }
}

@media (max-width: 768px) {
  .navbar {
    padding: var(--spacing-md) 0;
  }
  
  .navbar-container {
    padding: 0 var(--spacing-md);
  }
  
  .navbar-toggle {
    display: flex;
  }
  
  .navbar-menu {
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    flex-direction: column;
    gap: 0;
    background-color: var(--color-primary-dark);
    max-height: 0;
    overflow: hidden;
    transition: max-height var(--transition-base);
    list-style: none;
    padding: 0;
  }
  
  .navbar-menu.open {
    max-height: 500px;
  }
  
  .navbar-item {
    width: 100%;
    border-bottom: 1px solid rgba(255, 255, 255, 0.1);
  }
  
  .navbar-link {
    display: block;
    width: 100%;
    padding: var(--spacing-lg) var(--spacing-md);
    border-radius: 0;
  }
  
  .navbar-dropdown-menu {
    position: static;
    opacity: 1;
    visibility: visible;
    transform: none;
    background-color: var(--color-primary-dark);
    box-shadow: none;
    border-radius: 0;
    margin-top: 0;
    max-height: 0;
    overflow: hidden;
    transition: max-height var(--transition-base);
  }
  
  .navbar-dropdown.open .navbar-dropdown-menu {
    max-height: 300px;
  }
  
  .navbar-dropdown-item {
    padding: var(--spacing-md) var(--spacing-lg) var(--spacing-md) var(--spacing-2xl);
    border-bottom: none;
    background-color: rgba(255, 255, 255, 0.05);
  }
  
  .navbar-dropdown-link {
    color: rgba(255, 255, 255, 0.8);
  }
  
  .navbar-dropdown-link:hover {
    color: var(--color-accent);
  }
  
  .navbar-search {
    display: none;
  }
  
  .navbar-actions {
    gap: var(--spacing-md);
  }
  
  .navbar-cta {
    padding: var(--spacing-sm) var(--spacing-md);
    font-size: var(--font-size-xs);
  }
}

@media (max-width: 480px) {
  .navbar-brand {
    font-size: var(--font-size-base);
  }
  
  .navbar-logo {
    width: 32px;
    height: 32px;
    font-size: var(--font-size-base);
  }
  
  .navbar-link {
    font-size: var(--font-size-sm);
  }
  
  .navbar-cta {
    display: none;
  }
}

/* ===== 页面顶部间距 ===== */
body {
  padding-top: 70px;
}

@media (max-width: 768px) {
  body {
    padding-top: 60px;
  }
}

@media (max-width: 480px) {
  body {
    padding-top: 56px;
  }
}