function valid_mail(co) {
	return (/^[\w\.-]{2,}@[\w\.-]+\.[a-z]{2,5}$/i.test(co));
}

popup="";
function okno(arg,s,x,y) {
	if (popup == '[object]') {popup.close()} else {}
	scr_width = screen.availWidth;
	scr_height = screen.availHeight;
	left_align = eval(scr_width/2)-eval(x/2);
	top_align = eval(scr_height/2)-eval(y/2);
	popup=window.open(arg,'szczegoly','toolbar=0,location=0,direction=0,status=0,resize=0,menubar=0,scrollbars='+s+',width='+x+',height='+y+',left='+left_align+',top='+top_align);
}

/// <a href="javascript:okno('adres htmla.html',1, 400, 500);">sdfsfs</a>