.tongda_head {
  position: sticky;
  top: 0;
  left: 0;
  width: 100%;
  z-index: 99;
  transition: all 0.3s ease;
}

.tongda-navbar > .container {
  /* padding: 0 5rem; */
}

.tongda-navbar {
  transition: padding 0.3s ease;
  height: var(--header-height);
  display: flex;
  align-items: center;
  position: relative;
  z-index: 99;
  background: #fff;
  opacity: 0;
  visibility: hidden;
}

/* 入场动画 - JS 控制添加 class 触发 */
.tongda-navbar.tongda-navbar-enter {
  animation: tongda-head-slide-down 0.6s ease-out forwards;
}

@keyframes tongda-head-slide-down {
  from {
    opacity: 0;
    visibility: hidden;
    transform: translateY(-100%);
  }
  to {
    opacity: 1;
    visibility: visible;
    transform: translateY(0);
  }
}

.tongda-navbar-content {
  display: flex;
  align-items: center;
  justify-content: space-between;
  position: relative;
}

/* ==========================================
   Logo 
   ========================================== */

.tongda-logo-link .tongda-logo-vector {
  height: auto;
  max-height: 4.875rem;
  object-fit: contain;
}

/* ==========================================
   nav menu - desktop
   ========================================== */

.tongda-nav-menu {
  display: flex;
  align-items: center;
  gap: 2rem;
  flex: 1;
  justify-content: center;
}

.tongda-nav-item {
  position: relative;
  padding: 1.25rem 0;
  height: 100%;
}

.tongda-nav-link,
.tongda-dropdown-link,
.tongda-third-link,
.tongda-third-item.active a {
  color: var(--text-color);
  font-size: var(--font-size-18);
  font-weight: var(--font-weight-md);
  font-family: var(--font-family-orbitron);
  text-transform: capitalize;
  transition: color 0.3s ease;
  line-height: 150%;
  text-decoration: none;
}

.tongda-nav-item:hover .tongda-nav-link,
.tongda-nav-item.active .tongda-nav-link,
.tongda-dropdown-link:hover,
.tongda-dropdown-item.active .tongda-dropdown-link,
.tongda-third-link:hover {
  color: var(--color-primary) !important;
}

.tongda-nav-link {
  display: flex;
  align-items: center;
  gap: 5px;
}

/* 下拉箭头图标 */
.tongda-nav-link .iconfont {
  font-size: max(12px, 0.75rem);
  transition: transform 0.3s ease;
}

.tongda-nav-item.has-dropdown:hover .tongda-nav-link .iconfont {
  transform: rotate(180deg);
}

/* ==========================================
   下拉菜单
   ========================================== */

.tongda-dropdown-menu {
  position: fixed;
  /* top: 10px; */
  /* left: 0; */
  width: max-content;
  background: #fff;
  box-shadow: 0 0.625rem 1.875rem rgba(0, 0, 0, 0.15);
  min-width: 16.5rem;
  list-style: none;
  opacity: 0;
  visibility: hidden;
  transition: all 0.3s ease;
  z-index: 100;
  display: flex;
  flex-direction: column;
  align-items: flex-start;
  padding: 0px;
}

.tongda-nav-item.has-dropdown:hover .tongda-dropdown-menu {
  opacity: 1;
  visibility: visible;
}

.tongda-dropdown-item {
  width: 100%;
}

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

.tongda-dropdown-link {
  display: block;
  padding: 0.875rem 1.5rem;
  position: relative;
}

/* 第三层菜单样式 */
.tongda-dropdown-item.has-third-menu {
  position: relative;
}

.tongda-dropdown-item.has-third-menu a {
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.tongda-dropdown-link .iconfont {
  font-size: max(10px, 0.625rem);
  margin-left: auto;
  transition: transform 0.3s ease;
}

.tongda-dropdown-item.has-third-menu:hover .tongda-dropdown-link .iconfont,
.tongda-dropdown-item.has-third-menu:hover .tongda-dropdown-link svg {
  transform: rotate(-90deg);
}

.tongda-dropdown-item.has-third-menu svg {
  transform: scale(0.8);
  transform-origin: center;
  flex-shrink: 0;
}

.tongda-third-menu {
  position: absolute;
  left: 100%;
  top: 0;
  /* margin-left: 0.25rem; */
  background: rgba(255, 255, 255, 0.95);
  backdrop-filter: blur(15px);
  box-shadow: 0 0.625rem 1.875rem rgba(0, 0, 0, 0.15);
  min-width: 16.5rem;
  list-style: none;
  padding: 0.625rem 0;
  opacity: 0;
  visibility: hidden;
  transition: all 0.3s ease;
  z-index: 101;
}

.tongda-dropdown-item.has-third-menu:hover .tongda-third-menu {
  opacity: 1;
  visibility: visible;
}

.tongda-third-item {
  border-bottom: 1px solid rgba(0, 0, 0, 0.06);
}

.tongda-third-item:last-child {
  border-bottom: none;
}

.tongda-third-link {
  display: block;
  padding: 0.875rem 1.5rem;
  position: relative;
}

/* ==========================================
   右侧工具栏
   ========================================== */

.tongda-navbar-tools {
  display: flex;
  align-items: center;
  gap: 0.75rem;
}

.tongda-navbar-tools .em-quearys-inner {
  height: 100vh;
}

.tongda-language-selector,
.tongda-search-box {
  display: flex;
  align-items: center;
}

.tongda-search-box img {
  width: 21px;
  aspect-ratio: 1 / 1;
  object-fit: contain;
}

.tongda-search-box .em-header-quearys .em-quearys-menu {
  padding: 9px;
  border-radius: 50%;
  background-color: #d9d9d9;
  display: flex;
  align-items: center;
  justify-content: flex-start;
  position: relative;
  cursor: pointer;
}

.tongda-search-box .em-header-quearys .em-quearys-menu .qico.qico-search3 {
  color: var(--text-color);
  position: absolute;
  opacity: 0;
  z-index: 10;
}

/* 语言选择器样式调整 */

.lang-selector {
  width: 40px !important;
  background: #d9d9d9;
  border-radius: 50%;
  aspect-ratio: 1;
  display: flex;
  justify-content: center;
  align-items: center;
}

.lang-selector .current-lang {
  padding: 0 !important;
  height: auto;
  width: 100%;
  height: 100%;
  justify-content: center !important;
}

.lang-selector .lang-box {
  top: 50px;
}

.lang-selector .lang-box::before {
  display: none !important;
}

.tongda-language-selector .lang-selector .current-lang img {
  object-fit: contain;
  width: 27px;
  aspect-ratio: 1;
}
.tongda-language-selector .lang-selector .current-lang {
  color: var(--text-color);
}

.tongda-language-selector .lang-selector .current-lang em {
  display: none;
}

.tongda-language-selector .iconfont {
  display: none;
  color: var(--text-color) !important;
}

.tongda-inquiry-btn {
  margin-right: 0.75rem;
}

/* ==========================================
   移动端菜单按钮
   ========================================== */

.tongda-mobile-header {
  display: none;
}

.tongda-mobile-toggle {
  display: flex;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  gap: 6px;
  width: 24px;
  height: 24px;
  background: transparent;
  border: none;
  cursor: pointer;
  padding: 0;
  z-index: 10;
}

.tongda-mobile-toggle span {
  display: block;
  width: 100%;
  height: 2px;
  background-color: rgba(30, 63, 42, 1);
  transition: all 0.3s ease;
  transform-origin: center;
  position: relative;
}

/* 汉堡菜单激活时 - 变成关闭按钮 */
.tongda-mobile-toggle.active span:nth-child(1) {
  transform: translateY(8px) rotate(45deg);
}

.tongda-mobile-toggle.active span:nth-child(2) {
  opacity: 0;
  transform: scale(0);
}

.tongda-mobile-toggle.active span:nth-child(3) {
  transform: translateY(-8px) rotate(-45deg);
}

/* ==========================================
   移动端导航菜单
   ========================================== */

.tongda-mobile-menu-link,
.tongda-mobile-submenu-link {
  text-transform: capitalize;
  transition: all 0.3s ease;
  color: var(--text-color);
  font-size: var(--font-size-18);
  font-weight: var(--font-weight-md);
  text-decoration: none;
}

.tongda-mobile-menu-item.active .tongda-mobile-menu-link,
.tongda-mobile-submenu > li.active .tongda-mobile-submenu-link,
.tongda-mobile-third-submenu li.active .tongda-mobile-third-submenu-link {
  color: var(--color-primary);
}

.tongda-mobile-nav {
  position: fixed;
  inset: 0;
  left: 0;
  width: 100%;
  height: 100vh;
  background: rgba(17, 24, 39, 0.38);
  z-index: 100;
  overflow: hidden;
  opacity: 0;
  visibility: hidden;
  pointer-events: none;
  transition:
    opacity 0.35s ease,
    visibility 0.35s ease;
  animation: none;
}

.tongda-mobile-nav-panel {
  position: relative;
  margin-left: auto;
  width: min(25rem, 88vw);
  height: 100%;
  background: rgba(255, 255, 255, 0.97);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  overflow-y: auto;
  padding: 1rem;
  transform: translateX(100%);
  transition: transform 0.4s ease;
}

.tongda-mobile-nav-panel-tools {
  text-align: right;
}

.tongda-mobile-nav-close {
  color: var(--text-color);
  cursor: pointer;
  font-size: 1.5rem;
}

.tongda-mobile-nav.active {
  opacity: 1;
  visibility: visible;
  pointer-events: auto;
}

.tongda-mobile-nav.active .tongda-mobile-nav-panel {
  transform: translateX(0);
}

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

.tongda-mobile-menu-item {
  border-bottom: 1px solid rgba(51, 51, 51, 0.08);
}

.tongda-mobile-menu-item:nth-last-of-type(1) {
  border: none;
}

.tongda-mobile-menu-link-wrapper,
.tongda-mobile-submenu-link-wrapper {
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.tongda-mobile-menu-link {
  flex: 1;
  padding: 0.875rem 1rem 0.875rem 0;
  display: block;
}

/* 移动端第三层菜单激活时展开 */
.tongda-mobile-submenu > li.third-submenu-open .tongda-mobile-third-submenu {
  max-height: 31.25rem;
}
.tongda-mobile-submenu > li.active .tongda-third-submenu-toggle .iconfont {
  color: var(--text-color);
}

.tongda-mobile-menu-link:hover {
  color: var(--color-primary) !important;
  background: transparent;
}

/* 移动端子菜单切换按钮 */
.tongda-submenu-toggle {
  width: 2.75rem;
  height: 2.75rem;
  background: transparent;
  border: none;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: all 0.3s ease;
}

.tongda-submenu-toggle .iconfont {
  font-size: var(--font-size-18);
  color: var(--text-color);
  transition: transform 0.3s ease;
}

.tongda-mobile-menu-item.submenu-open .tongda-submenu-toggle .iconfont {
  transform: rotate(180deg);
}

.tongda-mobile-menu-item.submenu-open.active .tongda-submenu-toggle .iconfont {
  color: var(--color-primary);
}

/* 移动端子菜单 */
.tongda-mobile-submenu,
.tongda-mobile-third-submenu {
  list-style: none;
  margin: 0;
  padding: 0;
  max-height: 0;
  overflow: hidden;
  display: flex;
  flex-direction: column;
  gap: 10px;
  transition: max-height 0.4s ease;
}

.tongda-mobile-menu-item.submenu-open .tongda-mobile-submenu {
  max-height: 31.25rem;
}

.tongda-mobile-submenu-link {
  display: block;
  padding: 0 1rem 0 0;
  transition: all 0.3s ease;
  position: relative;
}

.tongda-mobile-submenu > li:nth-last-child(1) {
  padding-bottom: 10px;
}

/* 移动端第三层菜单样式 */
.tongda-mobile-submenu-link {
  flex: 1;
}

.tongda-third-submenu-toggle {
  background: transparent;
  border: none;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--text-color);
  transition: all 0.3s ease;
}

.tongda-third-submenu-toggle .iconfont {
  font-size: max(12px, 0.875rem);
  color: var(--text-color);
  transition: transform 0.3s ease;
}

.tongda-mobile-submenu
  > li.has-third-submenu.third-submenu-open
  .tongda-third-submenu-toggle
  .iconfont {
  transform: rotate(180deg);
}

.tongda-mobile-submenu
  > li.has-third-submenu.third-submenu-open
  .tongda-mobile-third-submenu {
  max-height: 31.25rem;
  /* padding: 10px 0; */
}

.tongda-mobile-third-submenu li:first-child {
  padding-top: 10px;
}

.tongda-mobile-third-submenu-link {
  display: block;
  padding: 0 0 0 0.75rem;
  color: var(--text-color);
  font-size: var(--font-size-18);
  text-decoration: none;
  transition: all 0.3s ease;
  position: relative;
}
/* 
.tongda-mobile-third-submenu-link:hover {
  color: var(--color-) !important;
} */

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

/* 平板和以下 */
@media (max-width: 1024px) {
  .tongda-navbar > .container {
    padding: 0 2rem;
  }

  .tongda-logo-container {
    flex: 1;
  }

  /* 隐藏桌面端导航菜单 */
  .tongda-nav-menu {
    display: none;
  }

  /* 显示移动端菜单按钮 */
  .tongda-mobile-header {
    display: flex;
    align-items: center;
    margin-left: 0.875rem;
  }
}

/* 小屏手机 */
@media (max-width: 576px) {
  .tongda-logo-icon .tongda-logo-vector {
    width: 10rem;
  }

  .tongda_head .tongda-inquiry-btn {
    display: none;
  }
}