function pokaz(nazwa) { document.all[nazwa].style.visibility='visible';}
function ukryj(nazwa) { document.all[nazwa].style.visibility='hidden';}   
function reset()
          { 
            document.all['start'].style.visibility='hidden';
            document.all['historia'].style.visibility='hidden';
            document.all['ostatnio'].style.visibility='hidden';
            document.all['baza'].style.visibility='hidden';
            document.all['oddzial'].style.visibility='hidden';
            document.all['klub'].style.visibility='hidden';
            document.all['wyprawy'].style.visibility='hidden';
            document.all['szkolenia'].style.visibility='hidden';
            document.all['sklep'].style.visibility='hidden';
            document.all['uslugi'].style.visibility='hidden';
            document.all['wypozyczalnia'].style.visibility='hidden';
           }