menu_oth = new Image();
  menu_oth.src = "img/rec_green.jpg";
  img_green =menu_oth.src ;

  menu_oth2 = new Image();
  menu_oth2.src = "img/rec_gray.jpg";
  img_grey =menu_oth2.src  ;

  function rozbal(menu){
    if ( document.getElementById(menu).style.display=="none" ){
      document.getElementById(menu).style.display = "block";
    }else{
      document.getElementById(menu).style.display = "none";
    }
  }

  function zvyrazni(menu){
    if(document.getElementById('aID_'+menu)){
      document.getElementById('aID_'+menu).style.listStyleImage="url("+img_green+")";
      document.getElementById('aID_'+menu).style.color="black";
      document.getElementById('aID_'+menu).style.fontWeight="bold";
    }
  }

  function zesvetli(menu){
    if (document.getElementById('aID_'+menu)){
      document.getElementById('aID_'+menu).style.listStyleImage="url("+img_grey+")";
      document.getElementById('aID_'+menu).style.color="#676B6C";
      document.getElementById('aID_'+menu).style.fontWeight="normal";
    }
  }

  function nastav(){
    document.getElementById(1).style.display="none";
    document.getElementById(2).style.display="none";
    document.getElementById(4).style.display="none";
    document.getElementById(5).style.display="none";
  }
  
  function kontrola(){
    re = /^[^.]+(\.[^.]+)*@([^.]+[.])+[a-z]{2,3}$/;

    if(form_mail.email.value.search(re)==0){
      return true;
    }else{
      alert("Nesprávný formát emailu");
      return false;
    }
  }