@media screen and (min-width: 620px) and (max-width: 768px) {
        #bg1{
            display: none;
        }
        #bg2{
            display: inline-block;
        }
        .hearder {
            width: 75%;
            margin: 0 auto;
            height: 3rem;
            line-height: 3rem;
        }
        .header-title {
            color: #004596;
            vertical-align: middle;
            font-size: 1rem;
        }
        .header-right li {
            list-style: none;
            float: right;
            margin: 0 2%;
            font-size: 0.9rem;
        }

        .service h2 {
            text-align: center;
            margin-top: 7rem;
            font-size: 2rem;
        }
        .pic {
            width: 100%;
            text-align: center;
        }
        /*.pic div{
            margin-left: 6rem;
            width: 6rem;
        }
        .pic div:nth-child(1){
            margin-left: 0;
        }*/
        .pic div{
            width: 40%;
            text-align: center;
            margin-top: 4rem;
        }
        .pic div img{
            width: 6rem;
        }
        .pic div p{
            margin-top: 2rem;
            font-size: 18px;
        }
         .aboutus h2 {
            text-align: center;
            margin-bottom: 1%;
            margin-top: 1%;
            font-size: 2rem;
        }
        .aboutus h5 {
            text-align: center;
            margin-top: 3rem;
            margin-bottom: 1rem;
        }
        .aboutus p {
            width: 580px;
            margin: 10px auto;
            text-indent: 2rem;
        }
        .contactus h2 {
            text-align: center;
            margin-bottom: 2%;
            font-size: 1.5rem;
        }
        .contactus>div{
            text-align: center;
            margin-top: 4rem;
        }
        .contactus>div>div:nth-child(1){
            float: left;
            margin-left: 30px;
        }
        .contactus>div>div:nth-child(2){
            float: right;
            margin-right: 30px;
        }
         .address-leftmar{
            margin-left: 0rem;
        }
        .email-address p {
            font-size: .8rem;
        }
        .code-li {
            position: relative;
        }
        .code-li:hover .dicode {
            display: block;
            
        }
        .dicode {
            background-color: #fff;
            width: 250px;
            height: 250px;
            padding: 25px;
            position: absolute;
            top: 90%;
            left: -96%;
            display: none;

        }
        .dicode>img {
            width: 100%;
            height: 100%;
        }
        .company-back{
            margin-top: 3rem;
            max-width: 768px;
            height: 668px;
            position: relative;
        }
        .footer{
            margin-top: 12rem;
        }
        .image-item{
            display: none;
        }
        .ipad-image-item{
            width: 580px;
            height: 30rem;
            background-color: #fff;
            margin: 20px auto;
            display: flex;
            flex-wrap: wrap;
            justify-content: space-between;
        }
        .ipad-left{
            width: 58%;
            height: 67%;
    
        }
        .ipad-right{
            width: 41%;
            height: 67%;
        }
        .ipad-bottom{
            width: 100%;
            height: 32%;
        }
        .ipad-left-img1{
            width: 100%;
            height: 62%;
            position: relative;
        }
        .ipad-left-img2{
            width: 50%;
            height: 37%;
            margin-top: 1%;
        }
        .ipad-left-img3{
            width: 49%;
            height: 37%;
            margin-top: 1%;
            float: right;
        }
        .ipad-right-img1{
            width: 100%;
            height: 50%;
        }
        .ipad-right-img2{
            width: 50%;
            height: 49%;
        }
        .ipad-right-img3{
            width: 49%;
            height: 49%;
            float: right;
        }
        .ipad-bottom-img1{
            width: 50%;
            height: 100%;
        }
        .ipad-bottom-img2{
            width: 49.5%;
            height: 100%;
            float: right;
        }
        .aboutus{
            padding-bottom: 4rem;
        }

        .tab-box{
            position: fixed;
            z-index: -1;
            top: 3rem;
            right: 0;
            width: 360px;
            height: 100%;
            background: #fff;
            opacity: 0;
            transition: opacity .8s;
        }
        .opa{
            opacity: .8;
            z-index: 10;
        }
        .tab-box p{
            font-size: 26px;
            color: #333;
            width: 80%;
            height: 80px;
            line-height: 80px;
            margin-left: 30px;
            border-bottom: 2px solid #ebebeb;
        }
        .tab-menu{
            float: right;
            color: #fff;
            margin-right: -50px;
            font-size: 20px;
            display: block;
        }
        .tab-menu img{
            width: 30px;
            height: 30px;
            border-radius: 50%;
            vertical-align: middle;
            margin-left: 70px;
            margin-right: -20px;
            margin-bottom: 5%;
        }
        .singout{
            width: 20px;
            height: 20px;
            background-color: #000;
            float: right;
            margin: 10px 10px 0 0;
            border-radius: 50%;
            opacity: .8;
        }

        .header-right{
            display: none;
        }

        .video-box{
            width: 580px; 
            height: 300px; 
            position: fixed; 
            top: 50%; 
            left: 50%; 
            transform: translate(-50%,-50%);
            display: none;
        }
        .mongolia{
            position: fixed;
            width: 100%;
            height: 100%;
            background-color: #333;
            opacity: .5;
            top: 0;
            left: 0;
            z-index: 1;
            display: none;
        }

    }