cookie_name = "customstyle";
if (document.cookie.length > 0) {
  start = document.cookie.indexOf(cookie_name + "=");
  if (start != -1) { 
    start = start + cookie_name.length + 1; 
    end = document.cookie.indexOf(";", start);
    if (end == -1) {
      end = document.cookie.length;
    }
    document.write("<link rel='stylesheet' href='" + unescape(document.cookie.substring(start, end)) + "' type='text/css' media='screen' />");
  } 
}