iNextPosition = 0;
iTotalPosition = 0;
window.onload = function() {
	new Effect.toggle('leftButton');	
}
function setIposition(){

	if(iNextPosition !=0){
		new Effect.Appear('rightButton');
		iNextPosition=iNextPosition+450;
		
		if(iNextPosition + 450 > 0){
			new Effect.Fade('leftButton');	
		}
	}else{
		
		iNextPosition = 0;
	}
}

function checkPosition(){
	if(Math.abs(iNextPosition) < Math.abs(iTotalPosition-450)){
		new Effect.Appear('leftButton');
		iNextPosition=iNextPosition-450;
		if(Math.abs(iNextPosition) >= Math.abs(iTotalPosition-450)){
			new Effect.Fade('rightButton');
		}
	}else{
		new Effect.Fade('rightButton');
	}	
}