ul.product-nav{
    list-style: none;
    padding-left: 5%;
    padding-right: 5%;
    padding-top: 40px; 
    padding-bottom: 40px;
    margin-bottom: 0px;
}

ul.product-nav::after{
    display: block;
    content: "";
    clear: both;
}

.product-nav li{
    float: left;
    width: 49%;
    height: 60px;
    margin-right: 2%; 
}



.product-nav li:last-of-type{
    margin-right: 0px;
}

.product-nav li>div{
    height: 50px;
    border: 1px solid #dddddd;
    line-height: 50px;
    text-align: center;
    font-size: 20px;
    color: black;
}


.product-nav li.active{
    background-image:url(../img/xuanzhong2.png);
    background-position: left top;
    background-size: 100% 100%;
    background-repeat: no-repeat; 
}

.product-nav li.active>div{
    color: white;
    border: none;
}

.product-nav li>div>a{
    color: inherit;
}


.product-content{
    padding: 10px 5% 40px 5%;
}

.product_title{
    height: 60px;
    line-height: 60px;
    font-size: 25px;
    color: #4a6cb6;
    text-align: center;
}

.product_title span{
    color: #b21b2e;
    position: relative;
    bottom: 10px;
}

.product_content p{
    font-size: 20px;
    line-height: 50px;
}

ul.product-list{
    margin: 0px;
    padding: 0px;
    list-style: none;
}

li.product-item{
    height: 260px;
    
    padding: 10px;
}

li.product-item a{
    border: 1px solid #eeeeee;
    line-height: 240px;
    text-align: center;
    display: inline-block;
    width: 100%;
    height: 100%;
}

li.product-item img{
    max-width: 100%;
    max-height: 240px;
}

/* md及以上 */
@media screen and (min-width:992px) {}

/* md以下 */
@media screen and (max-width:992px) {

    .product-nav li{
        float: left;
        width: 49%;
        height: auto;
        margin-right: 2%; 
    }
    
    
    
    .product-nav li:last-of-type{
        margin-right: 0px;
    }
    
    .product-nav li>div{
        height: auto;
        border: 1px solid #dddddd;
        line-height: 50px;
        text-align: center;
        font-size: 20px;
        color: black;
    }

    .product-nav li.active{
        background-image:none;
        background-position: left top;
        background-size: 100% 100%;
        background-repeat: no-repeat; 
    }
    
    .product-nav li.active>div{
        color: white;
        border: none;
        background-color: #2b53ae;
    }
}