function changeOpac(opacity, id)
{
    var object = $(id);
    object.style.opacity = (opacity / 100);
    object.style.MozOpacity = (opacity / 100);
    object.style.KhtmlOpacity = (opacity / 100);
    object.style.filter = "alpha(opacity=" + opacity + ")";
}

function HideLayers()
{
	for(var i=2; i<=4; i++)
	{
		$('desc'+i).style.display='none';
		$('menu'+i).removeClassName('over');
	}
	
}
var defaultTimer = 5000;
var selectedId = null;
var myTimeout = null;
function ContentFocus(id, timer)
{
	if(myTimeout != null) clearTimeout(myTimeout);
	if(selectedId!=null)
	{
		$('desc'+selectedId).style.display='none';
		$('menu'+selectedId).removeClassName('over');
	}
	selectedId = id;	
	$('desc'+id).style.display='block';
	changeOpac(0, 'desc'+id);
	new Effect.Opacity('desc'+id, {duration:0.5, from:0, to:1});
	$('menu'+selectedId).addClassName('over');
	
	id++;
	id = id>4?id=1:id;
	//myTimeout=setTimeout('ContentFocus('+id+','+defaultTimer+')', timer);
}