rdmimg=new Array();
rdmimg[0]="images/main_img01.jpg";
rdmimg[1]="images/main_img02.jpg";
rdmimg[2]="images/main_img03.jpg";
rdmimg[3]="images/main_img04.jpg";
rdmimg[4]="images/main_img05.jpg";
rdmimg[5]="images/main_img06.jpg";
rdmhead=Math.floor(rdmimg.length*Math.random());
rdmimg=rdmimg[Math.floor(rdmhead)];
document.write ('<style type="text/css">#main-img{background:url('+rdmimg+') top center no-repeat;height: 396px;text-align: center;}</style>');