function addClassName(el, sClassName) {
	var s = el.className;
	var p = s.split(" ");
	var l = p.length;
	for (var i = 0; i < l; i++) {
		if (p[i] == sClassName) {
			return;
		}
	}
	p[p.length] = sClassName;
	el.className = p.join(" ");
}

function removeClassName(el, sClassName) {
	var s = el.className;
	var p = s.split(" ");
	var np = [];
	var l = p.length;
	var j = 0;
	for (var i = 0; i < l; i++) {
		if (p[i] != sClassName) {
			np[j++] = p[i];
		}
	}
	el.className = np.join(" ");
}