function getColor(colorname)
{
var expires=new Date();
	expires.setTime(expires.getTime()+24*60*60*365*1000);
document.cookie = "colorname=" + escape(colorname)+ "; expires ="+ expires.toGMTString() ;
}

function getCookie(cookie_name)
{
var allcookies = document.cookie;
var cookie_pos = allcookies.indexOf(cookie_name);

// 如果找到了索引，就代表cookie存在，
// 反之，就说明不存在。
if (cookie_pos != -1)
{
// 把cookie_pos放在值的开始，只要给值加1即可。
cookie_pos += cookie_name.length + 1;
var cookie_end = allcookies.indexOf(";", cookie_pos);

if (cookie_end == -1)
{
cookie_end = allcookies.length;
}

var value = unescape(allcookies.substring(cookie_pos, cookie_end));
}

return value;
}

var cookies="";
cookies=getCookie("colorname");

if( cookies!=undefined && cookies!=null && cookies!="")
{
document.getElementById("stylecss").href="css/main"+cookies+".css";
}

function changecss(secolor)
{
document.getElementById("stylecss").href="css/main"+secolor+".css";
getColor(secolor);
}