function reveal(){


   var uA = navigator.userAgent;

   if(uA.indexOf("MSIE") > -1)
   {
      document.getElementById('tab1').style.display="block";  

      document.getElementById('tab2').style.display="block";  

      document.getElementById('tab3').style.display="block";  
   }
   else if(uA.indexOf("Gecko") > -1)
   {
       document.getElementById('tab1').style.display="none";  

       document.getElementById('tab2').style.display="none"; 

       document.getElementById('tab3').style.display="none"; 

   }

};