ranimg = new Array(); 
ranimg[0]="img/index_ph01.jpg"; 
ranimg[1]="img/index_ph02.jpg"; 
ranimg[2]="img/index_ph03.jpg"; 
ranimg[3]="img/index_ph04.jpg"; 
ranimg[4]="img/index_ph05.jpg"; 
xx = Math.floor(ranimg.length*Math.random()); 
ranimg = ranimg[Math.floor(xx)]; 
document.write ('<style type="text/css"><!--#bg01 {background-image: url("'+ ranimg +'");background-position: center;background-color: #333333;}--></style>');