window.addEventListener ('load', StartUp, false );

function StartUp () {
	//Center(document.getElementById('main'));
}

function Center(cosa) {
	if (cosa == null || cosa == "") cosa = this
	Ps = parseInt(cosa.parentNode.clientWidth);
	Os = parseInt(cosa.clientWidth);
	ms = (Ps - Os)/2;
	cosa.style.marginLeft = ms+"px";
	cosa.style.marginRight = ms+"px"
}