.head_nav ul.nav-tab {
    margin: 0 auto;
    position: relative;
}

.head_nav ul.nav-tab>li {
    float: left;
    width: 110px;
    text-align: center;
    line-height: 70px;
}

.head_nav ul.nav-tab>li>a {
    color: #000;
    font-size: 16px;
    text-decoration: none;
}

.head_nav ul.nav-tab>li>a:hover {
    border-bottom: 5px solid #ff6b00;
    padding-bottom: 20px;
    text-decoration: none;
    color: #ff6b00;
}
.head_nav ul.nav-tab>li#case_box>a:hover{
    border-bottom: 5px solid #ff6b00;
}
#nav ul li ul {
    display:block;
    opacity:1;
    filter: alpha(opacity=100);
}
#nav ul li .service-box-item .advantage-item {
    padding-left: 10px;
}
#nav ul li .service-box-item .advantage-item a {
    font-size: 18px;
    font-weight: bold;
    color: #333;
}
#nav ul li .service-box-item .advantage-item:hover a{
    color:#ff6b00;
    text-decoration:none;
}
#nav ul li .service-box-item .advantage-item:hover a.service-box-industry{
    color:#000;
    cursor:default;
}
#nav ul li .service-box-item .more-toknow a {
    font-size: 14px;
}
#nav ul li .service-box-item .more-toknow:hover a {
    color: #ff6b00;
    text-decoration: none;
}
.service-box-item p {
    padding-left: 10px;
    background: url(/templets/default/newimages/nav-list-style.jpg) no-repeat left center;
    font-size: 14px;
    color: #000;
}
.nav-tab-content>ul>li {
    float: left;
    line-height: 30px;
    color: #000;
    text-align: left;
}
#nav ul li ul.city_net {
    position: relative;
    width:945px;
    padding: 10px 40px;
}
#nav ul li ul.city_net>li {
    width: 90px;
    font-size: 12px;
    margin-right: 27px;
    line-height: 20px;
}
.city-office-item a {
    font-size: 14px;
    font-weight: bold;
}
.city-office-content:hover a {
    color: #ff6b00;
    text-decoration: none;
}
#nav ul li ul.city_net>li ul li {
    list-style-image:url(/templets/default/newimages/icon-city-net.jpg); 
    list-style-type: square;

} 
.city-office-content {
    margin-bottom: 16px;
}
#nav ul li ul.city_net>li:nth-of-type(7) {
    width: 100px;
    margin-right:22px;
}
#nav ul li ul.city_net>li:nth-of-type(7) ul li{
     width: 100px;
}
#nav ul li ul.city_net>li:last-of-type {
    margin-right: 0;
}
#nav ul li ul#case_net {
    position:relative;
     width: 765px;
    padding: 10px 40px 0;
    background: transparent;
}
#nav ul li ul#case_net li {
    width: 216px;
    height:auto;
    margin-right: 58px;
    line-height: 26px;
}
#case_box:hover #case_net {
    opacity:1;
    filter: alpha(opacity=100);
}
#case_box #case_net li a {
    height:auto;
    line-height:26px;
}
#case_box #case_net li:hover a{
    color:#000;
}
#case_box #case_net li:hover .case-demo a{
    color:#666;
}
#nav ul li:hover  ul#case_net li .case-demo a{
    white-space:nowrap; 
    overflow:hidden; 
    text-overflow:ellipsis;
}
#nav ul li ul#case_net li .case-demo {
    white-space:nowrap; 
    overflow:hidden; 
    text-overflow:ellipsis;
}
#nav ul li ul#case_net li a {
    font-size: 14px;
    color: #000;
}
#nav ul li ul#case_net li .case-demo a {
    font-size: 12px;
    color: #666;
}
#nav ul li ul#case_net li:nth-of-type(3n) {
    margin-right: 0;
}
#nav ul li ul#case_net li .case-industry:hover a,
#nav ul li ul#case_net li .case-demo:hover a {
    color: #ff6b00;
    text-decoration: none;
}
#nav ul li .more-toknow {
    text-align: right;
    margin-right: 40px;
    line-height: 40px;
}
#nav ul li .more-toknow a {
    color:#ff6b00;
}
#nav ul li .more-toknow:hover a,
#nav ul li .personal-position li:hover a {
    color: #ff6b00;
    text-decoration: none;
}
#nav ul li ul.about-us-box {
    width: 900px;
    padding: 10px 40px;   
}
#nav ul li ul.about-us-box li {
    height:auto;
    font-size: 14px;
    color: #000;
    line-height: 30px;
    text-align: left;
    margin-right: 62px;
    margin-left:0;
}
#nav ul li ul.about-us-box li:first-of-type {
    width: 150px;
}
#nav ul li ul.about-us-box li:nth-of-type(2){
    width: 130px;
}

    #nav ul li ul.about-us-box li:nth-of-type(3) {
        width: 170px;
    }

#nav ul li ul.about-us-box li:last-of-type {
    width: 200px;
    margin-right: 0;
}
#nav ul li ul.about-us-box .more-toknow {
    text-align: left;
    line-height: 40px;
}
#nav ul li ul.about-us-box .service-box-item .advantage-item {
    padding-left:0; 
}

#nav ul li ul.personal-position{
    width: 706px;
    padding: 10px 40px 0;
}

#nav ul li ul.personal-position li {
    width: 100px;
    height:auto;
    line-height: 30px;
    text-align: left;
    margin-right: 50px;
    margin-left:0;
    white-space:nowrap; 
    overflow:hidden; 
    text-overflow:ellipsis;
}
#nav ul li:hover ul.personal-position a,
#nav ul li ul.personal-position:hover
 {
    font-size:14px;
    color:#000;
    white-space:nowrap; 
    overflow:hidden; 
    text-overflow:ellipsis;
}
#nav ul li ul.personal-position li:hover a {
    color:#ff6b00;
}
#nav ul li ul.personal-position li:nth-of-type(5n) {
    margin-right: 0;
}
#nav ul li ul.personal-position li a {
    font-size: 14px;
    color: #000;
}
.service_box .nav-tab-content {
    transform: translate(-50%,0);
}
.nav-tab-content {
    display: none;
    position: absolute;
    left: 50%;
    transform: translate(-50%,0);
    background-color: rgb(255, 255, 255);
    opacity: 0.9;
    filter: alpha(opacity=90);
    z-index: 9999;
}

#nav ul li ul.service-item {
    padding: 14px 0 14px  40px;
    width:870px; 
}
.slogan {
    padding: 18px 0;
    border-top: 2px #ccc dashed;
    font-size: 24px;
    color: #000;
    line-height: 30px;
}
#nav ul li ul.service-item .more-toknow {
    text-align: left;
}
#nav ul li ul.service-item li {
        margin:0 36px 0 0;
        width: 130px;
        height:auto;
        text-align: left;
        line-height: 30px;
        float: left;
}
#nav ul li ul.service-item li:first-of-type {
    width: 150px;
    margin-right: 60px;
}
#nav ul li ul.service-item li:last-of-type {
    width:300px;
    margin-right: 0;
}
#nav ul li:hover ul {
    background: transparent;
    position: relative;
    opacity: 1;
    filter: alpha(opacity=100);
}
#nav ul li:hover ul li a {
            display: block;
            text-align: left;
            color:#ff6b00;
            padding: 0px;
            font-size: 15px;
}
#nav ul li:hover ul.service-item {
    padding: 14px 0 14px  40px;
    width:870px;
}
#nav ul li.city_box:hover ul.city_net {
    width:945px;
    padding: 10px 40px;
    background: transparent;
    position: relative;
    opacity:1;
    filter: alpha(opacity=100);
}
#nav ul li.city_box ul.city_net .city-office-content:hover .city-office-item a{
    color:#ff6b00;
} 
#nav ul .city_box:hover li a{
    height:auto;
    color:#000;
}
#nav ul li.city_box:hover ul.city_net ul {
    width: 100%;
    background:transparent;
    position: relative;
    opacity: 1;
    filter: alpha(opacity=100);
    padding: 0;
}
#nav ul li .city_net {
    display:block;
    background: transparent;
}
#nav ul li.city_box .city_net li, 
#nav ul .city_box:hover li {
    width: 90px;
    height:auto;
    margin-right: 27px;
    line-height: 20px;
    text-align:left;
}
#nav ul li.city_box .city_net li ul li{
        float:none;
}
#nav ul .city_box li .city-office-item a {
    font-size:14px;
    font-weight:bold;
}
.case-show p{
    width:140px;
    float:left;
}
#nav ul li:hover ul li .service-box-item  .case-show a{
    color:#000;
}
#nav ul li ul li .service-box-item  .case-show p:hover a{
    color:#ff6b00;
}
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