var toogle = 0;
function zapPod() {
  
  if (toogle == 0) {
  
      document.getElementById('podminky').style.visibility='visible';
      document.getElementById('podminky').style.height='300px';
      document.getElementById('odesilaci').disabled = false;
      
      toogle = 1;
    
  } else {
  
    document.getElementById('podminky').style.visibility='hidden';
    document.getElementById('podminky').style.height='10px';
    document.getElementById('odesilaci').disabled = true;
    
    toogle = 0;
  }

}