/* 小米汽车官网风格导航菜单样式 */

/* 基础变量 */
:root {
  /* 小米汽车官网配色 (参考: https://www.xiaomiev.com/) */
  --header-bg: #1a1a1a;           /* 深灰黑色背景，类似小米汽车官网 */
  --header-bg-scrolled: rgba(26, 26, 26, 0.95); /* 滚动时背景 */
  --text-primary: #ffffff;        /* 主文字色 */
  --text-secondary: rgba(255, 255, 255, 0.8); /* 次要文字色 */
  --text-hover: #ffffff;          /* 悬停文字色 */
  --accent-color: #ff6900;        /* 小米橙色 */
  --accent-hover: #ff8533;        /* 橙色悬停 */
  
  /* 尺寸 */
  --header-height: 64px;          /* 导航栏高度 */
  --header-height-scrolled: 60px; /* 滚动时高度 */
  --dropdown-height: 56px;        /* 二级菜单高度 */
  --container-width: 1360px;      /* 内容最大宽度 */
  
  /* 间距 */
  --spacing-xs: 4px;
  --spacing-sm: 8px;
  --spacing-md: 16px;
  --spacing-lg: 24px;
  --spacing-xl: 32px;
  
  /* 过渡效果 */
  --transition-fast: 0.2s ease;
  --transition-normal: 0.3s ease;
  --transition-slow: 0.4s ease;
  
  /* 阴影 */
  --shadow-light: 0 2px 8px rgba(0, 0, 0, 0.1);
  --shadow-medium: 0 4px 12px rgba(0, 0, 0, 0.15);
  --shadow-heavy: 0 8px 24px rgba(0, 0, 0, 0.2);
  --shadow-dropdown: 0 10px 40px rgba(0, 0, 0, 0.3);
}

/* 重置样式 */
.xiaomi-header * {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

/* ===== 头部导航栏 ===== */
.xiaomi-header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  height: var(--header-height);
  background-color: var(--header-bg);
  z-index: 1000;
  transition: all var(--transition-normal);
  width: 100%;
}

/* 滚动时样式 */
.xiaomi-header.scrolled {
  height: var(--header-height-scrolled);
  background-color: var(--header-bg-scrolled);
  backdrop-filter: blur(20px);
  box-shadow: var(--shadow-medium);
}

/* 导航容器 */
.nav-container {
  max-width: var(--container-width);
  height: 100%;
  margin: 0 auto;
  padding: 0 var(--spacing-lg);
  display: flex;
  align-items: center;
  justify-content: space-between;
  position: relative;
}

/* ===== Logo区域 ===== */
.nav-logo {
  flex-shrink: 0;
  margin-right: var(--spacing-xl);
}

.logo-link {
  display: flex;
  align-items: center;
  text-decoration: none;
  gap: var(--spacing-sm);
}

.logo-symbol {
  display: flex;
  align-items: center;
}

.logo-symbol img {
  display: block;
  transition: transform var(--transition-fast);
}

.logo-link:hover .logo-symbol img {
  transform: scale(1.05);
}

.logo-text {
  color: var(--text-primary);
  font-size: 20px;
  font-weight: 600;
  letter-spacing: 0.5px;
  transition: color var(--transition-fast);
}

.logo-link:hover .logo-text {
  color: var(--accent-color);
}

/* ===== PC端主导航 ===== */
.main-nav {
  flex: 1;
  display: flex;
  justify-content: center;
  height: 100%;
}

.nav-menu {
  display: flex;
  align-items: center;
  list-style: none;
  height: 100%;
  gap: 0;
}

/* 导航项 */
.nav-item {
  position: relative;
  height: 100%;
}

.nav-link {
  display: flex;
  align-items: center;
  justify-content: center;
  height: 100%;
  padding: 0 var(--spacing-lg);
  color: var(--text-secondary);
  text-decoration: none;
  font-size: 15px;
  font-weight: 400;
  transition: all var(--transition-fast);
  position: relative;
  white-space: nowrap;
}

.nav-link:hover {
  color: var(--text-hover);
  background-color: rgba(255, 255, 255, 0.05);
}

.nav-item.active .nav-link {
  color: var(--text-primary);
  font-weight: 500;
  background-color: rgba(255, 105, 0, 0.1);
}

/* 导航箭头（有下拉菜单时显示） */
.nav-arrow {
  display: inline-block;
  width: 0;
  height: 0;
  margin-left: var(--spacing-xs);
  border-left: 4px solid transparent;
  border-right: 4px solid transparent;
  border-top: 4px solid var(--text-secondary);
  transition: transform var(--transition-fast);
}

.nav-item.has-dropdown:hover .nav-arrow {
  border-top-color: var(--text-primary);
  transform: rotate(180deg);
}

/* ===== 二级下拉菜单 ===== */
.dropdown-menu {
  position: absolute;
  top: 100%;
  left: 0;
  right: 0;
  width: 100vw;
  margin-left: calc(-50vw + 50%);
  background-color: var(--header-bg);
  border-top: 1px solid rgba(255, 255, 255, 0.08);
  opacity: 0;
  visibility: hidden;
  transform: translateY(-10px);
  transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
  z-index: 1001;
  box-shadow: var(--shadow-dropdown);
}

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

.dropdown-container {
  max-width: var(--container-width);
  margin: 0 auto;
  width: 100%;
}

.dropdown-content {
  padding: var(--spacing-md) 0;
  display: flex;
  justify-content: center;
  gap: 0;
  flex-wrap: nowrap;
  overflow-x: auto;
  scrollbar-width: none;
  -ms-overflow-style: none;
}

.dropdown-content::-webkit-scrollbar {
  display: none;
}

/* 二级菜单项 */
.dropdown-item {
  display: flex;
  align-items: center;
  justify-content: center;
  padding: var(--spacing-sm) var(--spacing-xl);
  color: var(--text-secondary);
  text-decoration: none;
  font-size: 14px;
  font-weight: 400;
  transition: all var(--transition-fast);
  white-space: nowrap;
  flex: 0 0 auto;
  min-width: 140px;
  height: var(--dropdown-height);
  border-right: 1px solid rgba(255, 255, 255, 0.08);
  text-align: center;
  position: relative;
}

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

.dropdown-item:hover {
  color: var(--text-primary);
  background-color: rgba(255, 105, 0, 0.1);
}

.dropdown-item.active {
  color: var(--accent-color);
  font-weight: 500;
  background-color: rgba(255, 105, 0, 0.05);
}

.dropdown-item.active::before {
  content: '';
  position: absolute;
  bottom: 0;
  left: 50%;
  transform: translateX(-50%);
  width: 20px;
  height: 2px;
  background-color: var(--accent-color);
}

.item-text {
  display: block;
}

/* ===== 右侧功能区 ===== */
.nav-actions {
  display: flex;
  align-items: center;
  gap: var(--spacing-lg);
  margin-left: var(--spacing-xl);
}

.action-btn {
  display: flex;
  align-items: center;
  justify-content: center;
  text-decoration: none;
  transition: all var(--transition-fast);
}

/* 预约咨询按钮 */
.btn-test-drive {
  padding: 8px 24px;
  border: 1px solid rgba(255, 255, 255, 0.3);
  border-radius: 20px;
  color: var(--text-primary);
  font-size: 14px;
  font-weight: 500;
  background-color: transparent;
}

.btn-test-drive:hover {
  background-color: rgba(255, 255, 255, 0.1);
  border-color: var(--text-primary);
  transform: translateY(-1px);
  box-shadow: var(--shadow-medium);
}

/* 用户按钮 */
.btn-user {
  width: 36px;
  height: 36px;
  color: var(--text-secondary);
  border-radius: 50%;
}

.btn-user:hover {
  color: var(--accent-color);
  background-color: rgba(255, 255, 255, 0.05);
}

.user-icon {
  display: block;
}

/* ===== 移动端菜单按钮 ===== */
.mobile-menu-toggle {
  display: none;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  width: 40px;
  height: 40px;
  background: none;
  border: none;
  cursor: pointer;
  padding: 8px;
  gap: 5px;
}

.toggle-bar {
  display: block;
  width: 22px;
  height: 2px;
  background-color: var(--text-primary);
  transition: all var(--transition-fast);
}

.mobile-menu-toggle.active .toggle-bar:nth-child(1) {
  transform: rotate(45deg) translate(5px, 5px);
}

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

.mobile-menu-toggle.active .toggle-bar:nth-child(3) {
  transform: rotate(-45deg) translate(5px, -5px);
}

/* ===== 移动端菜单 ===== */
.mobile-menu {
  position: fixed;
  top: 0;
  right: -100%;
  width: 100%; /* 宽度100% */
  height: 100vh;
  background-color: var(--header-bg);
  z-index: 1002;
  transition: right var(--transition-normal) ease;
  overflow-y: auto;
  box-shadow: -4px 0 20px rgba(0, 0, 0, 0.3);
}

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

/* 移动端头部 */
.mobile-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 20px 24px;
  border-bottom: 1px solid rgba(255, 255, 255, 0.1);
  background-color: #151515; /* 更深的灰色，与小米汽车官网风格一致 */
}

.mobile-logo .logo-link {
  gap: var(--spacing-sm);
}

.mobile-logo .logo-text {
  font-size: 18px;
}

.mobile-close {
  background: none;
  border: none;
  color: var(--text-primary);
  cursor: pointer;
  padding: var(--spacing-sm);
  display: flex;
  align-items: center;
  justify-content: center;
  transition: transform var(--transition-fast);
}

.mobile-close:hover {
  transform: scale(1.1);
}

/* 移动端内容 */
.mobile-content {
  padding: var(--spacing-lg) 0;
}

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

/* 移动端导航项 */
.mobile-nav-item {
  border-bottom: 1px solid rgba(255, 255, 255, 0.1); /* 加深分隔线 */
}

.mobile-nav-item.special {
  border-bottom: none;
  margin-top: 20px;
  padding-top: 20px;
  border-top: 1px solid rgba(255, 255, 255, 0.1);
}

.mobile-nav-link {
  display: flex;
  align-items: center;
  justify-content: space-between; /* 左右对齐 */
  padding: 20px 24px;
  color: var(--text-primary);
  text-decoration: none;
  font-size: 17px; /* 增大字体 */
  font-weight: 400;
  transition: all var(--transition-fast);
  background-color: transparent;
}

.mobile-nav-link:hover {
  background-color: rgba(255, 255, 255, 0.05);
}

.mobile-nav-item.active .mobile-nav-link {
  color: var(--accent-color);
  background-color: rgba(255, 105, 0, 0.1);
  font-weight: 500;
}

/* 移除左边的小图标样式 */
.nav-icon {
  display: none; /* 隐藏左边小图标 */
}

.mobile-nav .nav-text {
  flex: 1;
  font-size: 17px; /* 增大字体 */
  letter-spacing: 0.3px;
  font-weight: 400;
}

/* 移动端子菜单 */
.submenu-toggle {
  font-size: 20px;
  color: rgba(255, 255, 255, 0.7); /* 提高箭头可见度 */
  transition: transform var(--transition-normal);
  margin-left: 8px;
}

.mobile-nav-item.has-submenu.active .submenu-toggle {
  transform: rotate(90deg);
  color: var(--accent-color);
}

.mobile-submenu {
  background-color: rgba(0, 0, 0, 0.2);
  max-height: 0;
  overflow: hidden;
  transition: max-height 0.3s cubic-bezier(0.4, 0, 0.2, 1);
  padding: 0;
}

.mobile-nav-item.has-submenu.active .mobile-submenu {
  max-height: 500px;
  padding: var(--spacing-sm) 0;
}

.mobile-submenu-item {
  display: block;
  padding: 16px 24px 16px 40px !important; /* 简化内边距，移除左边小圆点 */
  font-size: 15px !important;
  color: rgba(255, 255, 255, 0.7) !important;
  text-decoration: none;
  transition: all var(--transition-fast);
  position: relative;
  background-color: transparent;
  border-left: 2px solid transparent; /* 添加左边框用于选中状态 */
}

/* 移除小圆点 */
.mobile-submenu-item::before {
  display: none; /* 移除小圆点 */
}

.mobile-submenu-item:hover {
  color: var(--text-primary) !important;
  background-color: rgba(255, 255, 255, 0.05);
  border-left-color: rgba(255, 255, 255, 0.2); /* 悬停时显示左边框 */
}

.mobile-submenu-item.active {
  color: var(--accent-color) !important;
  background-color: rgba(255, 105, 0, 0.1);
  font-weight: 500;
  border-left-color: var(--accent-color); /* 激活时显示橙色左边框 */
}

/* 移除小圆点的激活状态 */
.mobile-submenu-item.active::before {
  display: none; /* 移除小圆点 */
}

.submenu-text {
  display: block;
}

/* 移动端咨询按钮 */
.btn-test-drive-mobile {
  display: flex;
  align-items: center;
  justify-content: center;
  margin: 0 24px;
  padding: 16px 24px;
  border: 1px solid var(--accent-color) !important;
  border-radius: 25px;
  color: var(--accent-color) !important;
  font-weight: 500;
  background-color: transparent !important;
  transition: all var(--transition-normal);
  font-size: 17px; /* 增大字体 */
}

.btn-test-drive-mobile:hover {
  background-color: var(--accent-color) !important;
  color: #000 !important;
  transform: translateY(-2px);
  box-shadow: 0 4px 12px rgba(255, 105, 0, 0.3);
}

.btn-test-drive-mobile .nav-icon {
  color: var(--accent-color);
  transition: color var(--transition-normal);
}

.btn-test-drive-mobile:hover .nav-icon {
  color: #000;
}

/* 移动端遮罩层 */
.mobile-overlay {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background-color: rgba(0, 0, 0, 0.5);
  z-index: 1001;
  opacity: 0;
  visibility: hidden;
  transition: all var(--transition-normal);
}

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

/* ===== 响应式设计 ===== */

/* 平板设备 */
@media (max-width: 1024px) {
  .nav-container {
    padding: 0 var(--spacing-md);
  }
  
  .nav-link {
    padding: 0 var(--spacing-md);
  }
  
  .dropdown-item {
    padding: var(--spacing-sm) var(--spacing-lg);
    min-width: 120px;
  }
}

/* 移动设备 */
@media (max-width: 768px) {
  /* 隐藏PC端导航 */
  .main-nav,
  .nav-actions {
    display: none;
  }
  
  /* 显示移动端菜单按钮 */
  .mobile-menu-toggle {
    display: flex;
  }
  
  .nav-container {
    justify-content: space-between;
    padding: 0 var(--spacing-md);
  }
  
  .nav-logo {
    margin-right: 0;
  }
  
  /* 隐藏PC端下拉菜单 */
  .dropdown-menu {
    display: none !important;
  }
  
  .nav-item.has-dropdown {
    position: static;
  }
  
  /* 调整头部高度 */
  .xiaomi-header {
    height: 60px;
  }
  
  .xiaomi-header.scrolled {
    height: 56px;
  }
  
  .logo-text {
    font-size: 18px;
  }
}

/* 小屏手机 */
@media (max-width: 480px) {
  .mobile-menu {
    width: 100%; /* 小屏幕也保持100%宽度 */
  }
  
  .mobile-header {
    padding: 16px 20px;
  }
  
  .mobile-nav-link {
    padding: 18px 20px;
    font-size: 16px;
  }
  
  .mobile-submenu-item {
    padding: 14px 20px 14px 36px !important; /* 调整内边距 */
    font-size: 15px !important;
  }
  
  /* 移除小圆点的响应式样式 */
  .mobile-submenu-item::before {
    display: none;
  }
  
  .mobile-submenu-item:hover {
    padding-left: 40px !important; /* 调整悬停时的内边距 */
  }
  
  .btn-test-drive-mobile {
    margin: 0 20px;
    padding: 14px 20px;
    font-size: 16px;
  }
}

/* 页面内容顶部间距 */
body {
  padding-top: var(--header-height);
}

/* 滚动时调整页面间距 */
.xiaomi-header.scrolled + * {
  padding-top: var(--header-height-scrolled);
}