function showHide() {
var nav = document.getElementById("nav");
var el = nav.getElementsByTagName("dd");
	for (var i = 0, j = el.length; i < j; i++) {
		if (el[i].className == "archive hide") {
		el[i].className = "archive";
		} else if (el[i].className == "archive") {
		el[i].className = "archive hide";
		}
	}
}