@media (max-width: 990px){
     .top-category-list,.serve,.news,.subnav{
        zoom:2;
    }
    .board_title{
        zoom:1.5;
    }
    .banner{
        margin-top: 135px;
    }
    .product .p_category li {
        width: 32%;
    }
    .product .p_category li a h2{
        font-size: 24px;
    }
    .top-category-menu{
        zoom:1.5;
    }
    .category-nav{
        zoom:2.5;
    }
    .top-category-list h5 a{
        font-size: 17px;
    }
}