function on (){
document.bt.src="/skin/frontend/default/default/images/menu/bt_uvod-h.jpg";}

function off (){
document.bt.src="/skin/frontend/default/default/images/menu/bt_uvod.jpg";}

function on1 (){
document.bt1.src="/skin/frontend/default/default/images/menu/bt_reklama-h.jpg";}

function off1 (){
document.bt1.src="/skin/frontend/default/default/images/menu/bt_reklama.jpg";}

function on2 (){
document.bt2.src="/skin/frontend/default/default/images/menu/bt_dielna-h.jpg";}

function off2 (){
document.bt2.src="/skin/frontend/default/default/images/menu/bt_dielna.jpg";}

function on3 (){
document.bt3.src="/skin/frontend/default/default/images/menu/bt_onas-h.jpg";}

function off3 (){
document.bt3.src="/skin/frontend/default/default/images/menu/bt_onas.jpg";}

function on4 (){
document.bt4.src="/skin/frontend/default/default/images/menu/bt_kontakt-h.jpg";}

function off4 (){
document.bt4.src="/skin/frontend/default/default/images/menu/bt_kontakt.jpg";}

function on5 (){
document.bt5.src="/skin/frontend/default/default/images/menu/bt_ucenie-h.jpg";}

function off5 (){
document.bt5.src="/skin/frontend/default/default/images/menu/bt_ucenie.jpg";}

function on6 (){
document.bt6.src="/skin/frontend/default/default/images/menu/bt_zdravie-h.jpg";}

function off6 (){
document.bt6.src="/skin/frontend/default/default/images/menu/bt_zdravie.jpg";}

function on7 (){
document.bt7.src="/skin/frontend/default/default/images/menu/bt_novinky-h.jpg";}

function off7 (){
document.bt7.src="/skin/frontend/default/default/images/menu/bt_novinky.jpg";}