a.bulle{
   position:relative;    z-index:0; background-color:#FAFAFA;
   color:#1818B6;
   text-decoration:none}

a.bulle:hover{z-index:30; background-color:#A4F5AE;}

a.bulle span{display: none}

a.bulle:hover span{display:block; position:absolute;
   top:2em; left:2em; width:10em;
   border:1px solid #6666CC;
   background-color:#F2EE78;
   color:#000000;
   text-align:center;
   font-weight:none;
 
      }