window.addEvent('domready', function(){ 
	 var totIncrement		= 0;
	 var increment			= 942;
	 var maxRightIncrement	= increment*(-1);
	 var fx = new Fx.Tween($('myList'), {duration: 1500, transition:'back:in:out'});

   
   
   
   $('previous').addEvent('click', function() {
        if(totIncrement < 0) {
            totIncrement += increment;
			fx.pause(); 
            fx.start('margin-left', totIncrement);
        }
    });

    $('next').addEvent('click', function() {
        if(totIncrement > maxRightIncrement) {
            totIncrement -= increment;
			fx.pause(); 
            fx.start('margin-left', totIncrement);
        }
    });
	 
});