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);