addLoadListener(init);

function init()
{
  var file = document.getElementById("file");
  file.className = "file";

  var yes = document.getElementById("yes");
  yes.onclick = showOptional;



  return true;
}

function showOptional()
{
  var file = document.getElementById("file");
 file.className = "show";

  return true;
}

/*function hideOptional()
{
  var optional = document.getElementById("file");
 file.className = "hidden";

  return true;
}*/

function addLoadListener(fn)
{
  if (typeof window.addEventListener != 'undefined')
  {
    window.addEventListener('load', fn, false);
  }
  else if (typeof document.addEventListener != 'undefined')
  {
    document.addEventListener('load', fn, false);
  }
  else if (typeof window.attachEvent != 'undefined')
  {
    window.attachEvent('onload', fn);
  }
  else
  {
    var oldfn = window.onload;
    if (typeof window.onload != 'function')
    {
      window.onload = fn;
    }
    else
    {
      window.onload = function()
      {
        oldfn();
        fn();
      };
    }
  }
}