$(function(){
	$(window).resize(centerContent);
	centerContent();
});

function centerContent()
{
	if($(window).height() < $('iframe').height()) {
		$('iframe').css({'margin-top': '0', 'top': '0'});
	} else {
		$('iframe').css({'margin-top': ($('iframe').height()/2) * -1, 'top': '50%'});
	}	
}