possibles = ['creditsDropUp','linksDropUp'];
function visi(nr)
{
	for(var i=0;i<possibles.length;i++)
	{
		if(possibles[i] != nr)
			document.getElementById(possibles[i]).style.visibility = 'hidden';
	}
	
	document.getElementById(nr).style.visibility = (document.getElementById(nr).style.visibility == 'visible') ? 'hidden' : 'visible';
}