var backgr1="/wcc/images/header1.jpg"
	var backgr2="/wcc/images/header2.jpg"
	var backgr3="/wcc/images/header3.jpg"
	var backgr4="/wcc/images/header4.jpg"	
	
	var cur=Math.round(8*Math.random())
	if (cur<=1)
	backgr=backgr1
	else if (cur<=3)
	backgr=backgr2
	else if (cur<=5)
	backgr=backgr3
	else
	backgr=backgr4	
	document.write('<style>#header{background-image: url('+backgr+');}</style>')