/* ========================================
   固定导航栏样式
   ======================================== */

header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  background: rgba(12, 14, 18, 0.9);
  border-bottom: 1px solid rgba(255, 255, 255, 0.08);
  box-shadow: 0 12px 30px rgba(0, 0, 0, 0.35);
  z-index: 1000;
  backdrop-filter: blur(18px);
  transition: transform var(--transition-base), background var(--transition-base);
}

header.scrolled {
  background: rgba(12, 14, 18, 0.98);
  border-bottom-color: rgba(255, 255, 255, 0.12);
}

.header-container {
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: nowrap;
  gap: var(--spacing-lg);
  padding: var(--spacing-sm) var(--spacing-lg);
  max-width: var(--container-2xl);
  margin: 0 auto;
  width: 100%;
  min-height: 72px;
  min-width: 0;
}

/* 标志与品牌 */
.logo {
  display: flex;
  align-items: center;
  gap: var(--spacing-sm);
  text-decoration: none;
  color: var(--color-text-light);
  font-size: var(--font-size-xl);
  font-weight: var(--font-weight-bold);
  transition: color var(--transition-fast);
}

.logo:hover {
  color: var(--color-secondary);
}

.logo-img {
  width: 40px;
  height: 40px;
  object-fit: contain;
}

.logo-text {
  display: flex;
  flex-direction: column;
  line-height: 1.2;
}

.logo-text-main {
  font-size: var(--font-size-lg);
  font-weight: var(--font-weight-bold);
}

.logo-text-sub {
  font-size: var(--font-size-xs);
  color: rgba(255, 255, 255, 0.6);
}

/* 导航菜单 */
header nav {
  flex: 1;
  margin-left: var(--spacing-xl);
  min-width: 0;
  overflow: visible;
}

.nav-menu {
  display: flex;
  list-style: none;
  gap: clamp(var(--spacing-sm), 2vw, var(--spacing-lg));
  margin: 0;
  padding: 0;
  flex-wrap: nowrap;
  align-items: center;
}

.nav-item {
  position: relative;
}

.nav-link {
  display: block;
  padding: var(--spacing-sm) var(--spacing-md);
  color: rgba(255, 255, 255, 0.7);
  text-decoration: none;
  font-weight: var(--font-weight-medium);
  transition: all var(--transition-fast);
  border-bottom: 2px solid transparent;
  letter-spacing: 0.02em;
  white-space: nowrap;
}

.nav-link:hover {
  color: var(--color-secondary);
  border-bottom-color: var(--color-secondary);
}

.nav-link.active {
  color: var(--color-secondary);
  border-bottom-color: var(--color-secondary);
}

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

.dropdown-menu {
  position: absolute;
  top: 100%;
  left: 0;
  background: #1F2128;
  border: 1px solid rgba(255, 255, 255, 0.08);
  border-radius: var(--border-radius-base);
  box-shadow: 0 16px 40px rgba(0, 0, 0, 0.4);
  min-width: 220px;
  list-style: none;
  margin: 0;
  padding: var(--spacing-sm) 0;
  opacity: 0;
  visibility: hidden;
  transform: translateY(-10px);
  transition: all var(--transition-fast);
  z-index: 1001;
}

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

.dropdown-item {
  padding: var(--spacing-sm) var(--spacing-lg);
  color: rgba(255, 255, 255, 0.8);
  text-decoration: none;
  display: block;
  transition: all var(--transition-fast);
}

.dropdown-item:hover {
  background-color: rgba(255, 255, 255, 0.05);
  color: var(--color-secondary);
  padding-left: var(--spacing-xl);
}

/* 右侧操作区 */
.header-actions {
  display: flex;
  align-items: center;
  gap: var(--spacing-md);
}

.header-phone {
  display: flex;
  align-items: center;
  gap: var(--spacing-xs);
  color: var(--color-secondary);
  font-weight: var(--font-weight-bold);
  text-decoration: none;
  transition: color var(--transition-fast);
}

.header-phone:hover {
  color: var(--color-accent);
}

.phone-icon {
  font-size: var(--font-size-lg);
}

.header-btn {
  padding: var(--spacing-xs) var(--spacing-md);
  background-image: linear-gradient(120deg, var(--color-secondary), var(--color-accent));
  color: var(--color-primary-dark);
  text-decoration: none;
  border-radius: var(--border-radius-base);
  font-weight: var(--font-weight-medium);
  transition: all var(--transition-fast);
  box-shadow: 0 10px 24px rgba(255, 193, 7, 0.3);
}

.header-btn:hover {
  transform: translateY(-2px);
  box-shadow: 0 14px 32px rgba(255, 152, 0, 0.4);
}

/* 移动菜单按钮 */
.mobile-menu-btn {
  display: none;
  background: none;
  border: none;
  font-size: var(--font-size-xl);
  color: var(--color-text-light);
  cursor: pointer;
  padding: var(--spacing-sm);
}

.mobile-menu-btn:hover {
  color: var(--color-secondary);
}

/* ========================================
   页面内容区域
   ======================================== */

main {
  margin-top: 80px;
  min-height: calc(100vh - 80px);
}

/* ========================================
   页脚样式
   ======================================== */

footer {
  background: linear-gradient(180deg, #0F1116 0%, #14171F 60%, #090A0D 100%);
  color: rgba(255, 255, 255, 0.8);
  padding: var(--spacing-2xl) var(--spacing-lg);
  margin-top: var(--spacing-2xl);
  position: relative;
  overflow: hidden;
}

footer::before {
  content: "";
  position: absolute;
  inset: 0;
  background: radial-gradient(circle at top right, rgba(255, 193, 7, 0.1), transparent 45%);
  pointer-events: none;
}

.footer-container {
  max-width: var(--container-2xl);
  margin: 0 auto;
  position: relative;
  z-index: 1;
}

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

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

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

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

.footer-section a {
  color: rgba(255, 255, 255, 0.7);
  text-decoration: none;
  transition: color var(--transition-fast);
}

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

.footer-bottom {
  border-top: 1px solid rgba(255, 255, 255, 0.15);
  padding-top: var(--spacing-lg);
  text-align: center;
  font-size: var(--font-size-sm);
  color: rgba(255, 255, 255, 0.6);
}

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

.footer-links a {
  margin: 0 var(--spacing-md);
  display: inline-block;
  color: rgba(255, 255, 255, 0.6);
}

.footer-links a:hover {
  color: var(--color-secondary);
}

/* ========================================
   响应式设计
   ======================================== */

@media (max-width: 1024px) {
  .nav-menu {
    gap: var(--spacing-sm);
  }
  
  .nav-link {
    padding: var(--spacing-xs) var(--spacing-sm);
  }
  
  .header-phone {
    display: none;
  }
}

@media (max-width: 768px) {
  .header-container {
    padding: var(--spacing-sm);
  }
  
  .logo-text-sub {
    display: none;
  }
  
  header nav {
    display: none;
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    background: #0F1116;
    border-bottom: 1px solid rgba(255, 255, 255, 0.08);
    margin-left: 0;
    padding: var(--spacing-md);
    width: 100%;
    white-space: normal;
    overflow: visible;
  }
  
  header nav.active {
    display: block;
  }
  
  .nav-menu {
    flex-direction: column;
    gap: var(--spacing-sm);
  }
  
  .dropdown-menu {
    position: static;
    opacity: 0;
    visibility: hidden;
    max-height: 0;
    overflow: hidden;
    transition: all var(--transition-fast);
    box-shadow: none;
    border: none;
    background-color: var(--color-background-light);
    margin-top: var(--spacing-sm);
  }
  
  .dropdown:hover .dropdown-menu {
    opacity: 1;
    visibility: visible;
    max-height: 500px;
    transform: none;
  }
  
  .mobile-menu-btn {
    display: block;
  }
  
  .header-actions {
    gap: var(--spacing-sm);
  }
  
  .header-btn {
    padding: var(--spacing-xs) var(--spacing-sm);
    font-size: var(--font-size-sm);
  }
  
  main {
    margin-top: 70px;
  }
  
  .footer-content {
    grid-template-columns: repeat(2, 1fr);
    gap: var(--spacing-lg);
  }
  
  .footer-section h3 {
    font-size: var(--font-size-base);
  }
}

@media (max-width: 480px) {
  .header-container {
    padding: var(--spacing-xs);
  }
  
  .logo {
    gap: var(--spacing-xs);
  }
  
  .logo-text-main {
    font-size: var(--font-size-base);
  }
  
  .header-actions {
    gap: var(--spacing-xs);
  }
  
  .footer-content {
    grid-template-columns: 1fr;
  }
  
  .footer-links a {
    margin: 0 var(--spacing-sm);
    font-size: var(--font-size-xs);
  }
}