function HideContent(d) {
document.getElementById(d).style.display = "none";
}
function ShowContent(d) {
document.getElementById(d).style.display = "block";
}
function ReverseDisplay(d) {
if(document.getElementById(d).style.display == "none") { document.getElementById(d).style.display = "block"; }
else { document.getElementById(d).style.display = "none"; }
}

function previewPlayStop (id, id2, timeout)
{
  document.getElementById(id).style.display='none';
  document.getElementById(id2).style.display='block';
  setTimeout ( function(){previewStop(id, id2)}, timeout );
}

function previewStop (id, id2)
{
  document.getElementById(id).style.display='block';
  document.getElementById(id2).style.display='none';
}