function temat(nr) {
  if(document.getElementById('odp_'+nr).style.display=="block") {
    document.getElementById('temat_link_'+nr).style.fontWeight="normal";
    document.getElementById('temat_'+nr).style.backgroundImage="url(/gfx/kropka.gif)";
    document.getElementById('linia_'+nr).src="/gfx/linia.gif";
    document.getElementById('odp_'+nr).style.display="none";
    }
  else {
    document.getElementById('temat_'+nr).style.backgroundImage="url(/gfx/kropka2.gif)";
    document.getElementById('temat_link_'+nr).style.fontWeight="bold";
    document.getElementById('linia_'+nr).src="/gfx/linia2.gif";
    document.getElementById('odp_'+nr).style.display="block";
  }
  return false;
}