document.getElementsByClassName = function(cl) {
var retnode = [];
var myclass = new RegExp('\\b'+cl+'\\b');
var elem = this.getElementsByTagName('*');
for (var j = 0; j < elem.length; j++) {
var classes = elem[j].className;
if (myclass.test(classes)) retnode.push(elem[j]);
}
return retnode;
}

function HideAll() {
var items = document.getElementsByClassName("optiton");
for (var j=0; j<items.length; j++) {
items[j].style.display = "none";
}
}
window.onload = function() {
	var show_item = "opt_1";
	document.getElementById(show_item).style.display = "block";
	var items = document.getElementsByClassName("title");
	for (var j=0; j<items.length; j++) {
	items[j].onclick = function() {
	var o = document.getElementById("opt_" + this.name);
	if (o.style.display != "block") {
	HideAll();
	o.style.display = "block";
	setCookie("show_item",this.name);
	}
	else {
	o.style.display = "block";
	}
	}
	}
};