function closeoverlay() {
  document.getElementById('overlay').style.display = 'none';
 
}
function openoverlay() {
  document.getElementById('overlay').style.display = 'block';    
}
function popunder()
{
	setTimeout('closeoverlay()', 15000);
	openoverlay();	
}


function addEvent(obj,type,fn)
{
	if (obj.addEventListener) 
	{
		obj.addEventListener( type, fn, false );
	} else if (obj.attachEvent) {
		obj["e"+type+fn] = fn;
		obj[type+fn] = function() { obj["e"+type+fn]( window.event ); }
		obj.attachEvent( "on"+type, obj[type+fn] );
	}
}

//addEvent(window,'load',popunder);