function winW() {
	if (window.innerWidth) return window.innerWidth;
	else if (document.documentElement && document.documentElement.clientWidth)
		return document.documentElement.clientWidth;
	else if (document.body && document.body.clientWidth)
		return document.body.clientWidth;
	else return null;
	}
	
function center() {	
	posx = Math.round((winW() - 930)/2);
	posf = posx - (posx % 9);
	if (posf < 9 ) {posf=9;}
		document.getElementById('main').style.left = posf-2+"px";
		document.getElementById('main').style.margin = "0px";
	}