var catfish;
function deploycatfish()

{
	catfish = document.getElementById('catfish');
	catfishheight = 90; // total height of catfish in pixels
	catfishoverlap = 30; // height of the 'overlap' portion only (semi-transparent)

	catfishtimeout = setTimeout(startcatfish, 300);
}

function startcatfish()

{
	catfishposition = 0; // catfishposition is expressed in percentage points (out of 100)
	catfishtimeout = setInterval(positioncatfish, 100);
}

function positioncatfish()
{
	catfishposition += 10;
	catfish.style.marginBottom = '-' + (((100 - catfishposition) / 100) * catfishheight) + 'px';
	if (catfishposition >= 100)
	{
		clearTimeout(catfishtimeout);
		catfishtimeout = setTimeout(finishcatfish, 1);
	}
}

function finishcatfish()
{
	catfish.style.marginBottom = '0';	
	document.body.parentNode.style.paddingBottom = (catfishheight - catfishoverlap) +'px';
}

addLoadEvent(deploycatfish);