var nav = function() {
	var sfEls = document.getElementById("nav").getElementsByTagName("li");
	for (var i=0; i<sfEls.length; i++) {
		sfEls[i].onmouseover = function() {
			this.className+=" over";
		}
		sfEls[i].onmouseout=function() {
			this.className = this.className.replace(new RegExp(" over\\b"), "");
		}
	}
}