/* 顶部导航栏 */
        .header {
            background: #fff;
            padding: 0 2%;
            height: 60px;
            display: flex;
            align-items: center;
            justify-content: space-between;
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.1);
    position: sticky;
    top: 0;
    z-index: 100;
        }

        .logo {
            display: flex;
            align-items: center;
            gap: 10px;
            cursor: pointer;
        }
.logo img {
    height:50px;
}
        .logo-icon {
            width: 40px;
            height: 40px;
            background: #1890ff;
            border-radius: 6px;
            display: flex;
            align-items: center;
            justify-content: center;
            color: #fff;
            font-size: 20px;
            font-weight: bold;
        }

        .logo-text {
            font-size: 22px;
            font-weight: 600;
            color: #262626;
        }

        .nav-menu {
            display: flex;
            gap: 40px;
            
        }

         .nav-item {
            color: #595959;
            text-decoration: none;
            font-size: 15px;
            font-weight: 500;
            transition: all 0.3s ease;
            padding: 20px 0;
            position: relative;
        }

        .nav-item.active {
            color: #1890ff;
        }

        .nav-item:hover::after {
            content: '';
            position: absolute;
            bottom: 0;
            left: 50%;
            width: 0;
            height: 3px;
            background: #333;
            transition: transform .3s ease, -webkit-transform .3s ease;
            transform: translateX(-50%);
        }

        .nav-item:hover::after, .nav-item.active::after {
            width: 100%;
        }

        .login-box {
            display: flex;
            gap: 12px;
            align-items: center;
        }

        .login-btn {
            padding: 8px 24px;
            background: transparent;
            color: #1890ff;
            border: 1px solid #1890ff;
            border-radius: 4px;
            font-size: 14px;
            font-weight: 500;
            cursor: pointer;
            transition: all 0.3s ease;
            text-decoration: none;
        }

        .login-btn:hover {
            background: #1890ff;
            color: #fff;
        }

        .register-btn {
            padding: 8px 24px;
            background: #1890ff;
            color: #fff;
            border: none;
            border-radius: 4px;
            font-size: 14px;
            font-weight: 500;
            cursor: pointer;
            transition: all 0.3s ease;
            text-decoration: none;
        }

        .register-btn:hover {
            background: #40a9ff;
            transform: translateY(-1px);
        }