var overlay = null;
function referenceAdd() {
	if ($('referenceAdd')) {
		function referenceAddResize(){
			overlay.setStyles({'top': window.getScrollTop(), 'height': window.getHeight()});
			$('referenceAdd').setStyles({'top': window.getScrollTop() + 45});
		}
		function referenceAddClose(){
			new Fx.Style($('referenceAdd'), 'opacity').start(0);
			overlay.setStyles({'top': 0, 'height': 0});
		}
		
		overlay = new Element('div', {'id': 'overlay'})
			.injectInside(document.body)
			.addEvent('click', function(e){ 
				var e = new Event(e);
				referenceAddClose();
				e.stop();
			}
		);
		referenceAddResize();
		
		$('referenceAdd').getElements('.close').addEvent('click', function(e){ 
			var e = new Event(e);
			referenceAddClose();
			e.stop();
		});
		window.addEvents({
			'resize': referenceAddResize,
			'scroll': referenceAddResize
		});
	}
}
window.addEvent('load', referenceAdd);