/* ==================== HEADER.CSS 最终整合版 ==================== */
:root {
    --ECS-blue: #005ca9;
    --ECS-blue-dark: #004b8a;
    --ECS-gray-light: #f7f7f7;
    --text-color: #535353;
    --ECS-dark: #333;
    --shadow-light: 0 2px 8px rgba(0,0,0,0.1);
    --shadow-medium: 0 4px 12px rgba(0,0,0,0.08);
}

/* ==================== 头部样式 ==================== */
.header {
    background: white;
    box-shadow: var(--shadow-light);
    padding: 12px 0;
    position: sticky;
    top: 0;
    z-index: 999;
    border-top: 3px solid var(--ECS-gray-light);
}

.header-inner {
    display: flex;
    justify-content: space-between;
    align-items: center;
    flex-wrap: wrap;
    
    gap: 2px ;
}

.logo img {
    height: 60px;
    margin-left: 40px;
}

/* ==================== 主菜单 ==================== */
.main-nav ul {
    list-style: none;
    display: flex;
    gap: 30px;
}

.main-nav ul li {
    position: relative;
}

.main-nav ul li a {
    color: #333;
    font-weight: 500;
    font-size: 18px;
    white-space: nowrap;
    padding: 8px 0;
    position: relative;
    transition: all 0.3s ease;
    text-decoration: none;
    font-weight: 500;
    letter-spacing: 0.5px; 

}

.main-nav ul li a::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 0;
    height: 2px;
    background-color: var(--ECS-blue);
    transition: width 0.3s ease;
}

.main-nav ul li a:hover {
    color: var(--ECS-blue);
    transform: translateY(-2px);
}

.main-nav ul li a:hover::after {
    width: 100%;
}

/* ==================== 语言切换 ==================== */
.lang {
    display: flex;
    align-items: center;
    gap: 8px;
    margin-left: -20px;
}

.lang button {
    background: none;
    border: none;
    font-weight: bold;
    cursor: pointer;
    color: #666;
    font-size: 14px;
    display: flex;
    align-items: center;
    padding: 4px 6px;
    border-radius: 4px;
    transition: 0.2s;
}

.lang button img {
    width: 18px;
    margin-right: 4px;
}

.lang button.active {
    color: var(--ECS-blue);
    background: rgba(0,92,169,0.08);
}

/* ==================== 汉堡按钮 ==================== */
.hamburger {
    display: none !important;
    cursor: pointer;
    padding: 10px 8px;
    border-radius: 6px;
    transition: all 0.25s ease;
}

.hamburger:hover {
    background-color: rgba(0,92,169,0.08);
}

.hamburger span {
    display: block;
    width: 24px;
    height: 3px;
    background: var(--ECS-blue);
    margin: 6px 0;
    border-radius: 3px;
    transition: all 0.3s ease;
}

.hamburger.active span:nth-child(1) {
    transform: translateY(8px) rotate(45deg);
}
.hamburger.active span:nth-child(2) {
    opacity: 0;
}
.hamburger.active span:nth-child(3) {
    transform: translateY(-8px) rotate(-45deg);
}

/* ==================== 移动端菜单 ==================== */
.mobile-menu {
    position: fixed !important;
    top: 0 !important;
    right: -280px !important;
    width: 280px !important;
    height: 100% !important;
    background: #005ca9 !important;
    z-index: 99999 !important;
    transition: 0.4s ease !important;
    padding: 30px 20px !important;
    color: #fff !important;
    overflow-y: auto !important;
    opacity: 1 !important;
    visibility: visible !important;
}
.mobile-menu.active {
    right: 0 !important;
}

.mobile-menu ul {
    list-style: none;
    margin-top: 30px;
}
.mobile-menu ul li {
    padding: 12px 0;
    border-bottom: 1px solid rgba(255,255,255,0.1);
}
.mobile-menu ul li a {
    color: #fff;
    font-size: 16px;
}

.close-menu {
    font-size: 24px;
    cursor: pointer;
    float: right;
}

/* ==================== PC 二级菜单 ==================== */
.main-nav .sub-menu {
    position: absolute;
    top: 100%;
    left: 0;
    min-width: 180px;
    background: #fff;
    box-shadow: 0 3px 10px rgba(0,0,0,0.1);
    border-radius: 6px;
    padding: 8px 0;
    list-style: none;
    display: none;
    z-index: 9999;
}
.main-nav .menu-item-has-children:hover .sub-menu {
    display: block;  
}
.main-nav .sub-menu li a {
    display: block;
    padding: 10px 18px;
    font-size: 16px;
    color: #333;
    text-decoration: none;
    font-weight: 400;
    letter-spacing: 0.2px; 
}
.main-nav .sub-menu li a:hover {
    background: #f7f7f7;
    color: var(--ECS-blue);
}

/* ==================== 移动端二级菜单 ==================== */
.mobile-menu .mobile-sub {
    display: none !important;
    padding-left: 20px !important;
    margin: 10px 0 0 !important;
    list-style: none !important;
    border-left: 1px solid rgba(255,255,255,0.2) !important;
}
.mobile-menu .mobile-sub.show {
    display: block !important;
}
.mobile-menu .mobile-sub li {
    border-bottom: none;
    padding: 8px 0;
}
.mobile-menu .mobile-sub li a {
    font-size: 15px;
    color: rgba(255,255,255,0.9);
}

/* ==================== 响应式 ==================== */
@media (max-width: 991px) {
    .main-nav { display: none !important; }
    .hamburger { display: block !important; }
}


/* 手机端二级菜单箭头 */
@media (max-width: 991px) {
  .mobile-menu li:has(.mobile-sub) > a {
    position: relative;
    padding-right: 24px !important;
  }

  /* 右侧箭头 */
  .mobile-menu li:has(.mobile-sub) > a::after {
    content: "▼";
    position: absolute;
    right: 0;
    top: 50%;
    transform: translateY(-50%);
    font-size: 12px;
    color: #fff;
    opacity: 0.9;
    transition: transform 0.3s ease;
  }

  /* 展开后箭头向上 */
  .mobile-menu li:has(.mobile-sub).open > a::after {
    transform: translateY(-50%) rotate(-180deg);
  }
}

/* 移动端二级菜单样式 */
.mobile-sub {
  display: none !important;
  padding-left: 20px;
  margin: 5px 0;
  list-style: none;
}
.mobile-sub.show {
  display: block !important;
}

.hamburger {
  cursor: pointer;
}

.close-menu {
  padding: 15px 20px;
  text-align: right;
  color: #fff;
  font-size: 20px;
  cursor: pointer;
}

.menu-arrow {
  position: absolute;
  right: 0;
  top: 50%;
  transform: translateY(-50%);
  font-size: 16px;
  color: #fff;
  opacity: 0.9;
  transition: transform 0.3s ease;
  cursor: pointer;
}

li.open .menu-arrow {
  transform: translateY(-50%) rotate(-180deg);
}