var aspasSimples = "'";

function alteraLayout()
{
	diferencaLeft=document.body.clientWidth-master.clientWidth;
	diferencaTop=document.body.clientHeight-master.clientHeight;
	if(diferencaLeft>0)
	{
		master.style.posLeft=diferencaLeft/2;
	}
	else
	{
		master.style.posLeft=0;
	}
	if(diferencaTop>0)
	{
		master.style.posTop=diferencaTop/2;
	}
	else
	{
		master.style.posTop=0;
	}	
}

alteraLayout();
document.body.attachEvent('onmouseenter',alteraLayout);