/* 导航栏 - 增强版 */
        header {
            position: fixed;
            top: 0;
            left: 0;
            width: 100%;
            z-index: 1000;
            background-color: rgba(26, 58, 95, 0.95);
            padding: 15px 0;
            transition: var(--transition);
        }
        header.scrolled {
            padding: 10px 0;
            box-shadow: 0 5px 20px rgba(0, 0, 0, 0.1);
        }
        .navbar {
            display: flex;
            justify-content: space-between;
            align-items: center;
        }
        .logo {
            font-size: 1.8rem;
            font-weight: 700;
            color: white;
            text-decoration: none;
            display: flex;
            align-items: center;
        }
        .logo i {
            margin-right: 10px;
            color: var(--accent-color);
        }
        .nav-links {
            list-style: none;
            display: flex;
        }
        .nav-links li {
            margin-left: 30px;
            position: relative;
        }
        .nav-links a {
            color: white;
            text-decoration: none;
            font-weight: 500;
            transition: var(--transition);
            display: flex;
            align-items: center;
        }
        .nav-links a i {
            margin-right: 8px;
        }
        .nav-links a:hover {
            color: var(--accent-color);
        }
        .nav-links li.has-dropdown:hover .dropdown-menu {
            opacity: 1;
            visibility: visible;
            transform: translateY(0);
        }
        .nav-links li.lang-drop:hover .lang-dropdown-menu {
            opacity: 1;
            visibility: visible;
            transform: translateY(0);
        }
        .dropdown-menu {
            position: absolute;
            top: 100%;
            left: 0;
            background-color: white;
            min-width: 320px;
            box-shadow: 0 10px 30px rgba(0, 0, 0, 0.15);
            border-radius: 8px;
            padding: 10px 0;
            list-style: none;
            opacity: 0;
            visibility: hidden;
            transform: translateY(10px);
            transition: var(--transition);
            z-index: 1000;
        }
        .dropdown-menu li {
            margin: 0;
        }
        .dropdown-menu a {
            color: var(--dark-color);
            padding: 12px 20px;
            display: block;
            transition: var(--transition);
        }
        .dropdown-menu a:hover {
            background-color: var(--light-color);
            color: var(--primary-color);
            padding-left: 25px;
        }

/* 语言切换下拉菜单 */
        .lang-drop {
            position: relative;
        }
        .lang-btn {
            color: #ffc107 !important;
            padding: 4px 12px;
            margin-top: -4px;
            border-radius: 4px;
            font-weight: 600;
            border: 2px solid #ffc107;
            cursor: pointer;
            white-space: nowrap;
            min-width: auto;
        }
        .lang-btn i {
            margin-right: 0 !important;
            color: inherit;
        }
        .lang-btn .fa-globe {
            font-size: 1rem;
        }
        .lang-btn .fa-chevron-down {
            margin-left: 2px !important;
            margin-right: 0 !important;
            font-size: 0.6rem;
        }
        .lang-btn:hover {
            background-color: rgba(255,193,7,0.15) !important;
        }
        .lang-dropdown-menu {
            position: absolute;
            top: 100%;
            right: 0;
            background-color: white;
            min-width: 140px;
            box-shadow: 0 10px 30px rgba(0, 0, 0, 0.15);
            border-radius: 8px;
            padding: 6px 0;
            opacity: 0;
            visibility: hidden;
            transform: translateY(8px);
            transition: all 0.25s ease;
            z-index: 1001;
        }
        .lang-dropdown-menu li {
            margin: 0;
        }
        .lang-dropdown-menu a {
            color: var(--dark-color);
            padding: 10px 20px;
            display: flex;
            align-items: center;
            gap: 10px;
            transition: var(--transition);
            font-weight: 500;
        }
        .lang-dropdown-menu a:hover {
            background-color: var(--light-color);
            color: var(--primary-color);
        }
        .lang-dropdown-menu a .lang-check {
            margin-left: auto;
            color: var(--secondary-color);
            font-size: inherit;
        }
        .lang-dropdown-menu a .lang-label {
            font-size: inherit;
            color: var(--gray-color);
        }

        .contact-btn {
            background-color: var(--accent-color);
            color: #000 !important;
            padding: 4px 20px;
            margin-top: -4px;
            border-radius: 4px;
            font-weight: 600;
            min-width: 130px;
        }
        .mobile-menu-btn {
            display: none;
            background: none;
            border: none;
            color: white;
            font-size: 1.5rem;
            cursor: pointer;
        }