.ustestcom-out-box{width:450px;height:300px;position:fixed;top:50%;left:50%;margin-top:-150px;margin-left:-225px;background-image:url('http://www.usaedu.net/statics/include/css/outbox.jpg');background-size:100% 100%;}
.ustestcom-out-box .hidden-x{cursor:pointer;position:absolute;right:17px;top:4px;width:25px;height:28px}
.ustestcom-out-box .go-btn{width:282px;height:44px;position:absolute;bottom:36px;left:84px;}