.nav{
    width: 100%;
    height: 48px;
    background: rgb(252,107,45);
}

.nav-ul li{
    float: left;
    text-align: center;
    width: 125px;
    height: 48px;
    font-size: 18px;
    color: #fff;
    line-height: 48px;
}

.drop-down-nav{
    height: 350px;
    display: none;
}
.drop-down-nav-section{
    width: 33.3%;
    height: 100%;
    box-sizing: border-box;
    float: left;
    padding-top: 20px;
    padding-right: 50px;
}
.drop-down-nav-subnav ul li{
    width: 100%;
    height: 38px;
    border-bottom: 1px #DEDEDE solid;
    text-align: left;
    padding-top: 5px;
    font-size: 16px;
    line-height: 38px;
}

.drop-down-nav-subnav{
    padding: 20px 70px 0 40px;
}
.drop-down-nav-section-imgwrap img{
    display: block;
    width: 100%;
    height: 150px;
}
.drop-down-nav-section-title{
    font-size: 14px;
    font-weight: bold;
    padding: 5px 0;
}
.drop-down-nav-section-content{
    font-size: 14px;
    line-height: 25px;
}