.main{
margin:?200px?auto;?
height:?270px;?
width:?800px;
border:?1px?solid?red;?
position:?relative;
}
.main_ul?a,.main_ul?img{
display:?block;???
}?
.main_ul{?
width:?800px;
height:?270px;?
overflow:?hidden;
}
.main_ul?.main_li{?
float:?left;
}
.main_btn{
top:?0;
height:?270px;
width:?100px;
position:?absolute;
z-index:?10;
}?
.btn_prev{??
background-color:?red;
left:?0;
}
.btn_next{??
right:?0;
background-color:?blue;
}