if(document.images){
       start1=new Image
       start2=new Image
       info1=new Image
       info2=new Image
       gal1=new Image
       gal2=new Image
       cen1=new Image
       cen2=new Image
       spa1=new Image
       spa2=new Image
       kon1=new Image
       kon2=new Image
       
       start1.src='images/button_01.gif'
       start2.src='images/button_01s.gif'
       info1.src='images/button_02.gif'
       info2.src='images/button_02s.gif'
       gal1.src='images/button_03.gif'
       gal2.src='images/button_03s.gif'
       cen1.src='images/button_04.gif'
       cen2.src='images/button_04s.gif'
       spa1.src='images/button_05.gif'
       spa2.src='images/button_05s.gif'
       kon1.src='images/button_06.gif'
       kon2.src='images/button_06s.gif'
       
       
       
}
function zmiana(polerys,nowyrys){
       if(document.images){
              document[polerys].src=eval(nowyrys+".src")
       }
}