document.observe('dom:loaded', function()
{
	$$("a.calc").each(function(el)
	{
		el.observe("click",function(ev)
		{
			ev.stop();

			var vyska = screen.height;
			var sirka = screen.width;

			var vyska_okna = 600;
			var sirka_okna = 800;

			var top = ((vyska / 2) - (vyska_okna / 2)) / 2;
			
			var left = (sirka / 2) - (sirka_okna / 2);
			
			var okno = window.open(el.href, "", "width="+sirka_okna+",height="+vyska_okna+",left="+left+",top="+top+",scrollbars=yes");
		})
	})
});