//------------------
function ShowForm(NomBloc){
  var Obj;
  //-- on affiche le fond
  Obj = document.getElementById('PAGE_FOND');
  if( Obj){
    with( Obj.style){
      position="absolute";
      display="";
      left = "0px";
      top  = "0px";
      zIndex= 10;
    }
  }
  //-- on affiche le formulaire
  Obj = document.getElementById(NomBloc);
  new Effect.Appear(NomBloc, { duration:0.5*2 });
  if( Obj){
    with( Obj.style){
      position="absolute";
      //display="";
      //left = "200px";
      top  = "100px";
      zIndex= 11;
    }
    try{Obj.focus();}catch(e){}
  }
}
//-----------------
function HideForm(NomBloc){
  var Obj;
  Obj = document.getElementById(NomBloc);
  //-- on masque le formulaire
  if( Obj){
    with( Obj.style){
      display="none";
    }
  }
  //-- on masque le fond  
  Obj = document.getElementById('PAGE_FOND');
  if( Obj){
    with( Obj.style){
      display="none";
    }
  }
}