@charset "gb2312";

@media screen and (min-width:320px) and (max-width:399px){
/*头部*/
header{line-height: 48px;height:48px;}
.logo{background-size:110px 28px;height:28px;width:110px; }
/*导航*/
.btn-nav span{height: 5px;width:30px;margin-top:5px;margin-bottom:5px;}

}
@media screen and (min-width:400px) and (max-width:479px){
/*头部*/
header{line-height: 60px;height:60px;}
.logo{background-size:125px 32px;height:32px;width:125px;}
/*导航*/
.btn-nav span{height: 7px;width:39px;margin-top:7px;margin-bottom:7px;}
}
@media screen and (min-width:480px) and (max-width:559px){
/*头部*/
header{line-height: 72px;height:72px;}
.logo{background-size:150px 38px;height:38px;width:150px;}
/*导航*/
.btn-nav span{height: 8px;width:47px;margin-top:8px;margin-bottom:8px;}
}
@media screen and (min-width:560px) and (max-width:639px){
/*头部*/
header{line-height: 84px;height:84px;}
.logo{background-size:177px 44px;height:44px;width:177px;}
/*导航*/
.btn-nav span{height: 10px;width:55px;margin-top:10px;margin-bottom:10px;}
}
@media screen and (min-width:640px) and (max-width:767px){
/*头部*/
header{line-height: 102px;height:102px;}
.logo{background-size:203px 50px;height:50px;width:203px;}
/*导航*/
.btn-nav span{height: 11px;width: 66px;margin-top: 11px;margin-bottom: 11px;}
}
@media screen and (min-width:768px){
/*头部*/
header{line-height: 115px;height:115px;}
.logo{background-size:244px 60px;height:60px;width:244px;}
/*导航*/
.btn-nav span{height: 13px;width: 75px;margin-top: 13px;margin-bottom: 13px;}
}