#site-box {
       width : 965px;
       border: 1px solid #e8d8cf;
       margin: 0 auto;
}

#a-box {
       
}

#b-box {
       float: left;    
       width: 648px;
       border-right: 1px solid #e8d8cf;
}

#c-box {
       float: right;    
       width: 315px; 
}

#d-box {
       clear: both;
       width: 963px;
       background-color: #e8d8cf;
 
}