function get_cookie(Name) {
  var search = Name + "="
  var returnvalue = "";
  if (document.cookie.length > 0) {
    offset = document.cookie.indexOf(search)
    // if cookie exists
    if (offset != -1) { 
      offset += search.length
      // set index of beginning of value
      end = document.cookie.indexOf(";", offset);
      // set index of end of cookie value
      if (end == -1) end = document.cookie.length;
      returnvalue=unescape(document.cookie.substring(offset, end))
      }
   }
  return returnvalue;
}
function set_cookie(Name, Value) {
  var content = Name + "=" + Value;
  document.cookie=content;
}


function toggle_cookie(Name) {
  var result = get_cookie(Name);
  var value = 0;
  if(result == 0) {value = 1;}
  set_cookie(Name, value);
}