@media (max-width: 1440px){



}

@media (max-width: 1024px){
   
}

@media (max-width: 768px){
    header.on{background: #fff;position: fixed;}
    header.on .head .menu span:before{background: #333;}
    .head .menu{width: 24px;height: 24px;display: block;position: absolute;top: 23px;right: 3%;    z-index: 110;}
    .head .menu span{display: block;padding: 3px 0; transition: all .4s ease;}
    .head .menu span:before{content: '';display: block;width: 24px;height: 2px;background: #333;border-radius: 1px; transition: all .4s ease; }
    .head .menu.on span:nth-child(1){transform: translateY(8px);}
    .head .menu.on span:nth-child(1):before{transform: rotate(45deg);}
    .head .menu.on span:nth-child(2){opacity: 0;}
    .head .menu.on span:nth-child(3){transform: translateY(-8px);}
    .head .menu.on span:nth-child(3):before{transform: rotate(-45deg);}

    .head ul{display: none;}
    .head .tel{display: none;}
    .nav_bg{display: none;position: absolute;top:80px;right: 0;z-index: 102;width: 100%;background: rgba(255,255,255,1);}
    .nav_bg ul{width:100%;background:#fff;color:#666666;}
    .nav_bg ul li{width: 100%;margin: 0 auto;border-top: 1px solid #e0e0e0;}
    .nav_bg ul li a{width: calc(100% - 70px);display: block;font-size: 16px;color: #666;line-height:48px;padding-left: 20px; float: left;}
    .nav_bg ul li span{display: block;width: 48px;height: 48px;float: right;background: url(../images/mt.png) no-repeat center;background-size: 50%;}
    .nav_bg ul li.active span{background: url(../images/mt-hover.png) no-repeat center;background-size: 50%;}
    .nav_bg ul li dl{display: none;}
    .nav_bg ul li dl dd{width: 100%;border-top: 1px solid #e0e0e0;}
    .nav_bg ul li dl dd a{display: block;float: none;padding-left: 40px;border-right: 0;}




}
@media (max-width: 480px){

}

@media (max-width: 375px){
    

}