function openwindow(strziel, strname, intwidth, intheight) {
	var attr = 'width='+intwidth+',height='+intheight+',left=100,top=100,screenx=0,screeny=0,resizable=no,toolbar=no,location=no,status=no,menubar=no,scrollbars=no,directories=no';
	window.open(strziel, strname, attr);
}
	
function showdiv(id)
{
  var objRef = document.getElementById(id);
  if(objRef.style.display=="none") {
    objRef.style.display="block";
    centerdiv(id);
  } else {
    objRef.style.display="none";
  }
}

function centerdiv(id)
{
	var pageX = (document.all)?document.body.offsetWidth:window.innerWidth;
  var pageY = (document.all)?document.body.offsetHeight:window.innerHeight;

  var objRef = document.getElementById(id);
  var objW = objRef.offsetWidth;
  var objH = objRef.offsetHeight;  

  objRef.style.left = ((pageX/2)-(objW/2))+"px";
  objRef.style.top = ((pageY/2)-(objH/2))+"px";
}