function otvor_okno(theURL) { 
  mx = Math.round((screen.width-710)/2);
  my = Math.round((screen.height-510)/2);
  var myWin2=window.open(theURL,"tr","status=yes,toolbar=no,directories=no,scrollbars=yes,location=no,resizable=yes,menubar=no,left="+mx+",top="+my+",width=700,height=500") . focus();
}

function otvor_okno_wide(theURL) { 
  mx = Math.round((screen.width-910)/2);
  my = Math.round((screen.height-260)/2);
  var myWin2=window.open(theURL,"tr","status=yes,toolbar=no,directories=no,scrollbars=yes,location=no,resizable=yes,menubar=no,left="+mx+",top="+my+",width=900,height=250") . focus();
}

function otvor_okno_big(theURL) { 
  mx = Math.round((screen.width-910)/2);
  my = Math.round((screen.height-510)/2);
  var myWin2=window.open(theURL,"tr","status=yes,toolbar=no,directories=no,scrollbars=yes,location=no,resizable=yes,menubar=no,left="+mx+",top="+my+",width=900,height=500") . focus();
}




function hide(object) {
    if (document.getElementById && document.getElementById(object) != null)  //ns6+ or ie5+
         node = document.getElementById(object).style.visibility='hidden';
    else if (document.layers && document.layers[object] != null)             //ns4
         document.layers[object].visibility = 'hidden';
    else if (document.all)						     //ie4+
         document.all[object].style.visibility = 'hidden';
}

function show(object) {
    if (document.getElementById && document.getElementById(object) != null)
         node = document.getElementById(object).style.visibility='visible';
    else if (document.layers && document.layers[object] != null)
        document.layers[object].visibility = 'visible';
    else if (document.all)
        document.all[object].style.visibility = 'visible';
}

function hideidt() {
    hide("idtnull"); hide("idtnotnull"); 
} 

function showidt(idt) {
    if (idt == 0) 
	show("idtnull");
    else
	show("idtnotnull");
}