function mysec(id)
{
   // var myElement = document.getElementById("basemap");
   // myElement.style.visibility="visible";
   map_off(id);
}

function myfunc(id)
{
   // var myElement = document.getElementById("basemap");
   // myElement.style.visibility="hidden";

   map_off(1);
   // map_off(2);
   map_on(id);
}

function map_on (id)
{
   var myElement = document.getElementById("Logo_"+id);
   myElement.style.visibility="visible";
}

function map_off (id)
{
   var myElement = document.getElementById("Logo_"+id);
   myElement.style.visibility="hidden";
}