function newEle(type, content, toNode) {
	var ele=document.createElement(type), i;
	for(i=3; i<arguments.length; i+=2) ele[arguments[i]]=arguments[i+1];
	if(content) ele.appendChild(document.createTextNode(content));
	if(toNode) toNode.appendChild(ele);
	return ele; }

function setStyle(title){
	var linkArr=document.getElementsByTagName('link'), i, link;
	for(i=0; link=linkArr[i]; i++) {
		if(/alt.*style/i.test(link.getAttribute('rel'))) {
			link.disabled=true;
			if(title==link.getAttribute('title')) link.disabled=false; }
	}
	createCookie('currStyle',title,(360*24*60*60*1000)); }

function createCookie(name, value, time) {
	document.cookie = name+"="+escape(value)+
		"; expires="+(new Date(new Date().getTime()+time)).toGMTString()+"; path=/"; }

function readCookie(name) {
	if( new RegExp(name+'\=([^;]*);','').test(document.cookie+';') ) return unescape(RegExp.$1);
	return null; }

window.onload=function(){
	var linkArr=document.getElementsByTagName('link'), link, i, theme=[], title, list, option;
	if(title=readCookie('currStyle')) setStyle(title);	
	for(i=0; link=linkArr[i]; i++) 
		if(/alt.*style/i.test(link.getAttribute('rel'))) theme.push(link);
	if(theme.length>0) {
		list=newEle('select','',document.getElementById('control'),'onchange', function(){setStyle(this.value)});
// default design
		newEle('option', 'home', list);
		for(i=0;i<theme.length;i++) {
			option=newEle('option', theme[i].title, list,'value',theme[i].title);
			if(option.value==title) option.selected=true; }			
	}}