function setActiveStyleSheet(title) {
 var i, a, main;
 for(i=0; (a = document.getElementsByTagName("link")[i]); i++) {
  if(a.getAttribute("rel").indexOf("style") != -1 && a.getAttribute("title")) {
   a.disabled = true;
   if(a.getAttribute("title") == title) a.disabled = false;
  }
 }
}

function getActiveStyleSheet() {
 var i, a;
 for(i=0; (a = document.getElementsByTagName("link")[i]); i++) {
  if(a.getAttribute("rel").indexOf("style") != -1 && a.getAttribute("title") && !a.disabled) return a.getAttribute("title");
 }
 return null;
}

function getPreferredStyleSheet() {
 var i, a;
 for(i=0; (a = document.getElementsByTagName("link")[i]); i++) {
  if(a.getAttribute("rel").indexOf("style") != -1
    && a.getAttribute("rel").indexOf("alt") == -1
    && a.getAttribute("title")
    ) return a.getAttribute("title");
 }
 return null;
}

function createCookie(name,value,days) {
 if (days) {
  var date = new Date();
  date.setTime(date.getTime()+(days*24*60*60*1000));
  var expires = "; expires="+date.toGMTString();
 }
 else expires = "";
 document.cookie = name+"="+value+expires+"; path=/";
}

function readCookie(name) {
 var nameEQ = name + "=";
 var ca = document.cookie.split(';');
 for(var i=0;i < ca.length;i++) {
  var c = ca[i];
  while (c.charAt(0)==' ') c = c.substring(1,c.length);
  if (c.indexOf(nameEQ) == 0) return c.substring(nameEQ.length,c.length);
 }
 return null;
}

window.onload = function(e) {
 var cookie = readCookie("style");
 var title = cookie ? cookie : getPreferredStyleSheet();
 setActiveStyleSheet(title);
}

window.onunload = function(e) {
 var title = getActiveStyleSheet();
 createCookie("style", title, 365);
}

var cookie = readCookie("style");
var title = cookie ? cookie : getPreferredStyleSheet();
setActiveStyleSheet(title);