#subNext_btn {
position:absolute; 
background-image: url(../images/nextsub.png); 
width: 33px; height: 
35px; left: 20px;
}
.button:hover {

}
#subPrev_btn {
position:absolute; 
background-image: url(../images/prevsub.png);
width: 33px;
 height: 35px; 
left: 53px;
}