function switchBg()
	{
		var css = 11; // 4 elements means values from 0 to 3

		var theTop = "background"; // the body CSS name
		//var theFooter = "footer"; // the footer id's CSS name

		var getbody = document.body; // get the body element
		//var footer = document.getElementById('footer'); // get the footer by id

		var value = Math.round(Math.random(987654321*123456789)*(css-1)); // generate a random value for the element classes from the default setup value
		getbody.className = theTop+value; // assign to the element the class name and the class name  value
		//footer.className = theFooter+value; // assign to the element the class name and the class name  value
	}