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);