ranimg = new Array();
ranimg[0]="images/top01.jpg";
ranimg[1]="images/top02.jpg";
ranimg[2]="images/top03.jpg";
ranimg[3]="images/top04.jpg";
ranimg[4]="images/top05.jpg";
ranimg[5]="images/top06.jpg";
xx = Math.floor(ranimg.length*Math.random());
ranimg = ranimg[Math.floor(xx)];
document.write ('<style type="text/css"><!--#background-div {background-image: url("'+ ranimg +'");}--></style>');