function okno(url,szer,wys,s)
{
var gora = (screen.width-1200)/2;
var bok = (screen.height-500)/2;
window.open(url,'_blank',"width="+szer+",height="+wys+",top="+gora+", left="+bok+",scrollbars="+s+",locationbar=no,menubar=no,personalbar=no,statusbar=yes,toolbar=no, resizable=no'");
}