a.info{
    position:relative; /*this is the key*/
    z-index:24;
    font-size: 12px;
    text-decoration:none}

a.info:hover{z-index:25; background-color:#fff}

a.info span{display: none}

a.info:hover span{ /*the span will display just on :hover state*/
    padding: 5px;
    display:block;
    position:absolute;
    top:-70px; left:100px; width:500px;
    border:1px solid #666;
    background-color:#ffcc00; color:#333;
    }