var isOver = null;
var isActive = null;

function setOver(id) {
	setOut();
	var s = "mainbutton_on";
	if (id == isActive)
		s += " active";
	el = document.getElementById(id);
	if (el)
		el.className = s;
	isOver=id;
}

function setOut() {
	if (isOver) {
		var s = "mainbutton";
		if (isOver == isActive)
			s += " active";
		el = document.getElementById(isOver);
		if (el)
			el.className=s;
		isOver=null;
	}
}

function setActive(id) {
	var s = 'mainbutton';
	setInactive();
	if (id == isOver)
		s += '_on';
	s += ' active';
	el = document.getElementById(id);
	if (el)
		el.className = s;
	isActive=id;
}

function setInactive() {
	if (isActive) {
		var s = "mainbutton";
		if (isOver == isActive)
			s += '_on';
		el = document.getElementById(isActive);
		if (el)
			el.className=s;
		isActive=null;
	}
}