.top{width:100%;}
.nav{width:100%; height:3.4rem; overflow:hidden; background:#FFF}
.nav li {width:24.8%; height:3.4rem; line-height:3.4rem; text-align:center; font-size:1.2rem; float:left; border-right:#DBDBDB solid 1px;}
.nav li.on{ border-right:0px;}

.db4{width:640px; height:94px;  position:fixed; left:50%; bottom:0px; margin-left:-320px}
.db4_1{width:180px; height:94px; float:left;background:#6BC086; text-align:center; color:#FFF}
.db4_1 img {width:44px; margin-top:6px;}
.db4_2{width:276px; height:70px; padding-top:24px; float:left; background:#FF951B; border:#ABDBBA solid 1px; border-top:0px; border-bottom:0px; position:relative; text-align:center; color:#FFF}
.db4_2 i { width:138px; height:118px; position:absolute; left:74px; top:-80px; z-index:1}
.db4_2 i img { width:100%}
.db4_2 span{ z-index:2}