$(document).ready(function() {
	self.setInterval("changeBackground()",4000);
	//.fadeIn("slow");

});
function changeBackground() {
	var id = Math.floor(Math.random()*6);
		
	$('#deco').css( 'background', function() { 		
		return 'url(./img/ma-uri0'+id+'.gif)' ;
	});
}