body{
    background-color: #fff;
    color: #434343;
    min-width: 1200px;
}

/* common */
.con{
    margin: 0 auto;
}
.con2{
    margin: 0 0;
    margin-left: 3%;
}
.marginTop{
    margin-top: 98px;
}

/* 方框标题 */
.com_title{
    text-align: center;
}
.com_tit_CN{
    display: inline-block;
    width: 122px;
    height: 37px;
    line-height: 37px;
    text-align: center;
    background-color: #434343;
    color: #fff;
    font-size: 14px;
    position: relative;
}
.com_tit_CN::after{
    position: absolute;
    left: 4px;
    top: 4px;
    content: '';
    width: 112px;
    height: 27px;
    border: 1px solid #fff;
}
.com_tit_EN{
    font-size: 14px;
    line-height: 35px;
    font-weight: bold;
}

/* header */
.head_content{
    position: fixed;
    top: 0;
    left: 0;
    z-index: 999;
    width: 100%;
    height: 94px;
    background-color: #fff;
    border-bottom:4px solid #bfbfbf;
}
.head{
    width: 1540px;
    height: 94px;
}
.logo a,.logotl a,.logo_3d3s,.logo3d3s a{
    display: inline-block;
    width: 100%;
    height: 100%;
}
.logo img,.logotl img,.logo_3d3s,.logo3d3s img{
    width: 100%;
    height: 100%;
}
.logo{
    width: 179px;
    height: 60px;
    margin-top: 17px;
    margin-right: 51px;
}
.logo_3d3s{
    width: 185px;
    height: 48px;
    margin-top: 23px;
    margin-left: 130px;
}
.logotl{
    width: 179px;
    height: 60px;
    margin-top: 17px;
    margin-right: 51px;
}
.logo3d3s{
    width: 185px;
    height: 48px;
    margin-top: 23px;
    margin-right: 45px;
}
.navbar{
    height: 94px;
}
.navbar li{
    float: left;
    width: 130px;
    height: 100%;
    text-align: center;
    cursor: pointer;
    position: relative;
}
.navbar li > a{
    display: inline-block;
    width: 100%;
    height: 20px;
    margin-top: 37px;
    border-left: 1px solid #434343;
    box-sizing: border-box;
    color: #434343;
    font-family: '宋体';
}
.navbar li:first-child > a{
    border:none;
    height: 100%;
    line-height: 92px;
    margin-top: 0;
}
.navbar li:hover,.navbar li.active{
    background: -webkit-linear-gradient(to bottom,#e9e9e9 0%,#c0c0c0 50%,#e9e9e9 100%);
    background: -moz-linear-gradient(to bottom,#e9e9e9 0%,#c0c0c0 50%,#e9e9e9 100%);
    background: -ms-linear-gradient(to bottom,#e9e9e9 0%,#c0c0c0 50%,#e9e9e9 100%);
    background: -o-linear-gradient(to bottom,#e9e9e9 0%,#c0c0c0 50%,#e9e9e9 100%);
    background: linear-gradient(to bottom,#e9e9e9 0%,#c0c0c0 50%,#e9e9e9 100%);
}
.navbar li:hover .nav_toggle{
    display: block;
}

.nav_toggle{
    position: absolute;
    top:94px;
    left: 0;
    width: 100%;
    box-sizing: border-box;
    background-color: #fff;
    border: 1px solid #b5b5b5;
    border-top: 4px solid #b5b5b5;
    box-shadow: 2px 2px 6px #b5b5b5;
    display: none;
}
.nav_toggle a{
    display: block;
    width: 100%;
    height: 32px;
    border-bottom: 1px solid #b5b5b5;
    line-height: 32px;
    color: #434343;
    font-family: '宋体';
    font-size: 16px;
}
.nav_toggle a:last-child{
    border-bottom: none;
}
.nav_toggle a:hover,.nav_toggle a.current{
    background-color: #434343;
    color: #fff;
}


/*footer*/
.footer{
    height: 52px;
    background-color: #434343;
    color: #fff;
    font-size: 14px;
    font-weight: bold;
    line-height: 52px;
    text-align: center;
}

@media only screen and (max-width: 1600px){

    .head_content{
        height: 74px;
    }
    .head{
        width: 1180px;
        height: 74px;
    }
    .logo{
        width: 120px;
        height: 40px;
        margin-top: 17px;
        margin-right: 60px;
    }
    .logo_3d3s{
        width: 146px;
        height: 38px;
        margin-top: 18px;
        margin-left: 50px;
    }
    .logotl{
        width: 120px;
        height: 40px;
        margin-top: 17px;
        margin-right: 60px;
    }
    .logo3d3s{
        width: 138px;
        height: 36px;
        margin-top: 19px;
        margin-right: 42px;
    }
    .navbar{
        height: 74px;
    }
    .navbar li{
        width: 110px;
    }
    .navbar li > a{
        height: 20px;
        margin-top: 27px;
    }
    .navbar li:first-child > a{
        line-height: 72px;
    }
    .nav_toggle{
        top:74px;
    }

    .marginTop{
        margin-top: 78px;
    }

}