Java vertical center but only vertical

Hi,

Usually I use javascript for my site to center them perfectly in center and to not have cropping on smaller windows.

Now for my site I want to just simply vertical align but my script do both. How can I fix the script to have vertical align in center but horizontal at left.

Thx

function align()
{

	var lmt = document.getElementById('centrage');
	var container = document.documentElement;

	if(lmt && container)
	{
	    var containerHeight;
	    if (container.innerWidth)
	    {
            containerHeight = container.innerHeight;
		}
		else
		{
            containerHeight = container.clientHeight;
		}
	    var lmtHeight;
	    if (lmt.innerWidth)
	    {
            lmtHeight = lmt.innerHeight;
		}
		else
		{
            lmtHeight = lmt.offsetHeight;
		}
		var y = Math.ceil((containerHeight - lmtHeight) / 2);
		if(y < 0)
		{
			y = 0;
		}
		lmt.style.position = "relative";
		lmt.style.top = y + "px";
	}
	if (document.getElementById)
	{
		document.body.style.visibility = 'visible';
	}

}

function addevent(obj,evt,fn,capt){
	if(obj.addEventListener)
	{
		obj.addEventListener(evt, fn, capt);
		return true;
	}
	else if(obj.attachEvent)
	{
		obj.attachEvent('on'+evt, fn);
		return true;
	}
	else return false;
}

if (document.getElementById && document.getElementsByTagName)
{
	addevent(window, 'load', align, false);
	addevent(window, 'resize', align, false);
}