function change(_event)
{
	var target=_event.target;
	if (!target)
		target=_event.srcElement;

	target=target.parentNode.parentNode;

	if (target.className=="open")
		target.className="closed";
	else if (target.className=="open-last")
		target.className="closed-last";
	else if (target.className=="closed")
		target.className="open";
	else if (target.className=="closed-last")
		target.className="open-last";
}