/* 简洁大气导航样式 */
.header {
    background: #fff;
    box-shadow: 0 1px 3px rgba(0, 0, 0, 0.1);
    position: sticky;
    top: 0;
    z-index: 1000;
}

.nav-wrapper {
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: 80px;
    padding: 0 20px;
}

/* Logo 样式 */
.logo a {
    display: flex;
    align-items: center;
    text-decoration: none;
}

.logo img {
    height: 60px;
    width: auto;
    transition: transform 0.3s ease;
}

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

/* 桌面端导航 */
.nav-menu {
    display: block;
}

.nav-menu ul {
    display: flex;
    list-style: none;
    margin: 0;
    padding: 0;
    gap: 0;
}

.nav-menu a {
    display: block;
    padding: 25px 30px;
    text-decoration: none;
    color: #666;
    font-size: 16px;
    font-weight: 500;
    border-bottom: 3px solid transparent;
}

.nav-menu a:hover {
    color: #333;
    border-bottom-color: #EF4444;
}

.nav-menu a.active {
    color: #EF4444;
    border-bottom-color: #EF4444;
}

.nav-menu a:focus {
    outline: none;
    background: rgba(239, 68, 68, 0.05);
}

/* 移动端按钮 - 默认隐藏 */
.mobile-toggle {
    display: none;
    flex-direction: column;
    justify-content: center;
    width: 30px;
    height: 30px;
    background: none;
    border: none;
    cursor: pointer;
    padding: 0;
}

.mobile-toggle span {
    display: block;
    height: 3px;
    width: 100%;
    background: #333;
    margin: 3px 0;
    transition: 0.3s;
}

.mobile-toggle.active span:nth-child(1) {
    transform: rotate(45deg) translate(6px, 6px);
}

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

.mobile-toggle.active span:nth-child(3) {
    transform: rotate(-45deg) translate(7px, -7px);
}

/* 移动端菜单 - 默认隐藏 */
.mobile-menu {
    display: none;
    background: #fff;
    border-top: 1px solid #eee;
}

.mobile-menu.active {
    display: block;
}

.mobile-menu-content {
    padding: 20px 0;
}

.mobile-menu-item {
    display: block;
    padding: 15px 30px;
    text-decoration: none;
    color: #666;
    font-size: 16px;
    font-weight: 500;
    border-left: 3px solid transparent;
}

.mobile-menu-item:hover {
    background: #f8f9fa;
    color: #333;
}

.mobile-menu-item.active {
    color: #EF4444;
    border-left-color: #EF4444;
    background: #fef2f2;
}

.mobile-menu-item:focus {
    outline: none;
    background: #f8f9fa;
}

/* 响应式设计 */
@media (max-width: 768px) {
    .nav-wrapper {
        height: 70px;
        padding: 0 15px;
    }
    
    .logo img {
        height: 45px;
    }
    
    /* 移动端隐藏桌面导航 */
    .nav-menu {
        display: none !important;
    }
    
    /* 移动端显示汉堡包按钮 */
    .mobile-toggle {
        display: flex !important;
    }
}

@media (max-width: 480px) {
    .nav-wrapper {
        padding: 0 12px;
    }
    
    .logo img {
        height: 38px;
    }
}