function afficheSection(numPart,nomCat){ 

 document.getElementById(nomCat).style.display = "block"; 
  document.getElementById("cache"+numPart.toString()).style.display = "block";
document.getElementById("voir"+numPart.toString()).style.display = "none"; 
 }
 function cacheSection(numPart,nomCat){ 
 document.getElementById(nomCat).style.display = "none"; 
 document.getElementById("cache"+numPart.toString()).style.display = "none";
 document.getElementById("voir"+numPart.toString()).style.display = "block";
 }