html, body {margin:0;padding:0;background:#000;}

#website {position:absolute;width:100%;height:800px;z-index:11;top:0;right:0;}

#primeiro {float:left;margin:0;background:url(../images/bg01.jpg) no-repeat;width:370px;height:300px;}
#segundo {float:right;margin:0;background:url(../images/bg02.jpg);background-repeat: no-repeat;background-position: top right;width:370px;height:300px;}
#terceiro {float:left;margin:0;background:url(../images/bg03.jpg);background-repeat: no-repeat;background-position: bottom left;width:370px;height:300px;}
#quarto {float:right;margin:0;background:url(../images/bg04.jpg);background-repeat: no-repeat;background-position: bottom right;width:370px;height:300px;}