.tooltip{
width: 200px; color:#fff;
font: 9pt Trebuchet MS, Arial,sans-serif;
text-decoration:none;text-align:center}

.tooltip span.top{padding: 25px 8px 0;
    background: url(bt.gif) no-repeat top}

.tooltip b.bottom{padding:3px 8px 10px;color: #0f0f0f;
    background: url(bt.gif) no-repeat bottom; font-size:0px;}