var DOM = (document.getElementById)?true:false;
var NN = (document.layers)?true:false;
var IE = (document.all)?true:false;
var NN6 = DOM;
var Opera = DOM && window.opera;

function hideObject(el)
{
  el.style.display = 'none'
  if (NN) el.visibility = "hide";
  else el.style.visibility = "hidden";
}

function showObject(el)
{
  el.style.display = 'block'
  if (NN) el.visibility = "show"
  else el.style.visibility = "visible";
}

function $(objname)
{
  if (IE) return document.all[objname];  
  if (NN) return getNNElement(null, objname);
  if (DOM) return document.getElementById(objname);
}  

function OpenCalendar()
{
  hideObject($('google_calendar_opener'))
  showObject($('google_calendar'))
}

function CloseCalendar()
{
  showObject($('google_calendar_opener'))
  hideObject($('google_calendar'))
}