root = Class.extend({
	_container_id: null,

	init: function(id)
	{
		this._container_id = id;

		// center id
		this.center();

	},
	
	center: function ()
	{
		var x = (($(window).width() - $('#' + this._container_id).width()) / 2);
		var y = (($(window).height() - $('#' + this._container_id).height()) / 2);

		$('#' + this._container_id).css({position: 'absolute', left: x, top: y, 'z-index' : '100'});
	}
});