header {
    background-color: #fff;
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.1);
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 1000;
}

.header-container {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 10px 20px;
    max-width: 1400px;
    margin: 0 auto;
}

.logo {
    height: 50px;
}

.logo img {
    height: 100%;
}

.nav-menu {
    display: flex;
    align-items: center;
}

.nav-menu > li {
    position: relative;
    margin: 0 15px;
}

.nav-menu > li > a {
    font-size: 14px;
    font-weight: 600;
    color: #1e3a5f;
    padding: 15px 10px;
    display: block;
    transition: color 0.3s ease;
}

.nav-menu > li > a:hover {
    color: #d4af37;
}

.nav-menu > li.has-submenu > a::after {
    content: '';
    display: inline-block;
    width: 0;
    height: 0;
    border-left: 4px solid transparent;
    border-right: 4px solid transparent;
    border-top: 4px solid #1e3a5f;
    margin-left: 5px;
    vertical-align: middle;
}

.submenu {
    position: absolute;
    top: 100%;
    left: 0;
    background-color: #fff;
    box-shadow: 0 4px 20px rgba(0, 0, 0, 0.15);
    min-width: 200px;
    opacity: 0;
    visibility: hidden;
    transform: translateY(-10px);
    transition: all 0.3s ease;
    z-index: 1001;
}

.nav-menu > li:hover .submenu {
    opacity: 1;
    visibility: visible;
    transform: translateY(0);
}

.submenu li {
    padding: 0;
}

.submenu li a {
    padding: 12px 20px;
    font-size: 13px;
    color: #333;
    display: block;
    transition: background-color 0.3s ease, color 0.3s ease;
    border-bottom: 2px solid transparent;
}

.submenu li a:hover {
    background-color: #f5f5f5;
    color: #1e3a5f;
    border-bottom: 2px solid #1e3a5f;
}

.submenu li a.active {
    background-color: #1e3a5f;
    color: #d4af37;
}

.nav-menu > li > a.active {
    color: #d4af37;
}

.header-right {
    display: flex;
    align-items: center;
}

.search-icon {
    font-size: 20px;
    color: #1e3a5f;
    cursor: pointer;
    margin-right: 15px;
    transition: color 0.3s ease;
}

.search-icon:hover {
    color: #d4af37;
}

.search-box {
    position: absolute;
    top: 100%;
    right: 60px;
    background-color: #fff;
    box-shadow: 0 4px 20px rgba(0, 0, 0, 0.15);
    padding: 10px;
    display: none;
    z-index: 1002;
}

.search-box.active {
    display: block;
}

.search-box form, .search-box .search-form {
    display: flex;
    align-items: stretch;
    gap: 0;
    height: 38px;
}

.search-box input {
    flex: 1;
    width: 220px;
    height: 38px;
    padding: 0 15px;
    border: 1px solid #ddd;
    border-right: none;
    border-radius: 4px 0 0 4px;
    font-size: 14px;
    line-height: 36px;
    outline: none;
    box-sizing: border-box;
}

.search-box input:focus {
    border-color: #1e3a5f;
}

.search-box input:focus + .search-submit-btn {
    border-color: #1e3a5f;
}

.search-submit-btn {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 38px;
    height: 38px;
    padding: 0;
    border: 1px solid #1e3a5f;
    border-radius: 0 4px 4px 0;
    background-color: #1e3a5f;
    color: #fff;
    font-size: 14px;
    cursor: pointer;
    box-sizing: border-box;
    transition: background-color 0.3s ease, border-color 0.3s ease;
}

.search-submit-btn:hover {
    background-color: #d4af37;
    border-color: #d4af37;
}

.search-submit-btn i {
    font-size: 14px;
}

.lang-switch {
    padding: 8px 16px;
    background-color: #1e3a5f;
    color: #fff;
    font-size: 13px;
    font-weight: 600;
    border-radius: 4px;
    transition: background-color 0.3s ease;
}

.lang-switch:hover {
    background-color: #0f2439;
    color: #d4af37;
}

.mobile-menu-toggle {
    display: none;
    font-size: 24px;
    cursor: pointer;
}

@media (max-width: 1024px) {
    .nav-menu {
        position: fixed;
        top: 0;
        right: 0;
        width: 280px;
        height: 100vh;
        background-color: #fff;
        box-shadow: -4px 0 20px rgba(0, 0, 0, 0.15);
        flex-direction: column;
        padding: 80px 20px 20px;
        overflow-y: auto;
        transform: translateX(100%);
        transition: transform 0.3s ease;
        z-index: 999;
    }
    
    .nav-menu.active {
        display: flex;
        transform: translateX(0);
    }
    
    .nav-menu > li {
        margin: 0;
        border-bottom: 1px solid #eee;
    }
    
    .nav-menu > li > a {
        padding: 15px 10px;
        display: flex;
        justify-content: space-between;
        align-items: center;
    }
    
    .nav-menu > li.has-submenu > a::after {
        display: inline-block;
        width: 8px;
        height: 8px;
        border-right: 2px solid #1e3a5f;
        border-bottom: 2px solid #1e3a5f;
        transform: rotate(45deg);
        margin-left: 5px;
        transition: transform 0.3s ease;
    }
    
    .nav-menu > li.has-submenu.open > a::after {
        transform: rotate(-135deg);
    }
    
    .submenu {
        position: static;
        opacity: 1;
        visibility: hidden;
        max-height: 0;
        transform: none;
        box-shadow: none;
        margin: 0;
        padding: 0;
        border-left: none;
        background-color: #f9f9f9;
        overflow: hidden;
        transition: max-height 0.3s ease, padding 0.3s ease;
    }
    
    .nav-menu > li.has-submenu.open > .submenu {
        visibility: visible;
        max-height: 300px;
        padding: 10px 0;
    }
    
    .submenu li a {
        padding: 12px 20px;
        color: #666;
        border-bottom: none;
    }
    
    .submenu li a:hover {
        background-color: #f0f0f0;
        color: #1e3a5f;
        border-bottom: none;
    }
    
    .mobile-menu-toggle {
        display: block;
        color: #1e3a5f;
        margin-left: 15px;
    }
    
    .search-box {
        right: 20px;
    }
    
    .header-right {
        position: relative;
        z-index: 1001;
    }
    
    .nav-overlay {
        position: fixed;
        top: 0;
        left: 0;
        right: 0;
        bottom: 0;
        background-color: rgba(0, 0, 0, 0.5);
        opacity: 0;
        visibility: hidden;
        transition: opacity 0.3s ease, visibility 0.3s ease;
        z-index: 998;
    }
    
    .nav-overlay.active {
        opacity: 1;
        visibility: visible;
    }
}