(function () {
	var scroller = new Fx.Scroll(window, {transition: Fx.Transitions.Quad.easeInOut, duration : 500});
	
	
	window.addEvent('load',function () {
		$('back_to_top').addEvent('click',
			function(event) {
				event = new Event(event).stop();
				scroller.toElement($('head'));
			});
		});
})();