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);