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);