//------------------------------------------------------------------------------
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 createStyleSheetCookie(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 readStyleSheetCookie(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 = readStyleSheetCookie('style');
   var title = cookie ? cookie : getPreferredStyleSheet();
   setActiveStyleSheet(title);
}
//------------------------------------------------------------------------------
window.onunload = function(e){
   var title = getActiveStyleSheet();
   createStyleSheetCookie('style', title, 365);
}
//------------------------------------------------------------------------------
 