// JavaScript Document
function camada1( sId ) {
       var sDiv = document.getElementById( sId );
       if( sDiv.style.visibility == "visible" ) {
         sDiv.style.visibility = "hidden";
       } 
	   else { sDiv.style.visibility = "visible";
       }
     }
	 
function camada2( sId ) {
       var sDiv = document.getElementById( sId );
       if( sDiv.style.visibility == "hidden" ) {
         sDiv.style.visibility = "visible";
       } 
	   else { sDiv.style.visibility = "hidden";
       }
     }