function centreContent()
{
	var windowHeight = document.body.clientHeight;
	var pageObj = document.getElementById("page");

	if ( windowHeight > 600 )
	{
		var pageTopMargin = Math.round( (windowHeight-600)/2 );
		pageObj.style.top = pageTopMargin.toString()+"px";
	}
	else
	{
		pageObj.style.top = "0px";
	}
}