function checkform()
 {
    var flaga = false;
    var form = document.forms[0];

              if (form.imie_i_nazwisko.value=="")
                {
                document.getElementById("nazwisko").style.color = 'red';
                document.getElementById("nazwisko").style.setProperty('font-weight','bold',null);
                flaga = true;
                }
              if (form.e_mail.value=="" || form.e_mail.value.indexOf('@', 0) == -1 || form.e_mail.value.indexOf('.', 0) == -1)
                {
                document.getElementById("e_mail").style.color = 'red';
                document.getElementById("e_mail").style.setProperty('font-weight','bold',null);
                flaga = true;
                }
              if (form.uwagi.value=="")
                {
                document.getElementById("uwagi").style.color = 'red';
                document.getElementById("uwagi").style.setProperty('font-weight','bold',null);
                flaga = true;
                }

        if (flaga == false)
            {
            form.submit();
            }
        else
            {
            document.getElementById("error").style.setProperty('visibility','visible',null);
            }
 }