function getClientWidth()
{
  return document.compatMode=='CSS1Compat' && !window.opera?document.documentElement.clientWidth:document.body.clientWidth;
}

var width = getClientWidth();
if(width<1030&&width>1000){
    var style = document.createElement("link");
    style.setAttribute("rel", "stylesheet");
    style.setAttribute("type","text/css");
    style.setAttribute("href","/wp-content/themes/twentyeleven/1024.css");
    document.getElementsByTagName('head')[0].appendChild(style);
    if(mac){
        var macOS = document.createElement("link");
        macOS.setAttribute("rel", "stylesheet");
        macOS.setAttribute("type","text/css");
        style.setAttribute("href","/wp-content/themes/twentyeleven/macOS_1024.css");
        document.getElementsByTagName('head')[0].appendChild(macOS);
    }

}