dd#monitorDef{ top: 65px; left: 114px; }
dd#monitorDef a{ position: absolute; width: 73px; height: 69px; text-decoration: none; }
dd#monitorDef a span{ display: none; }
dd#monitorDef a:hover{ position: absolute; background: transparent url(office.jpg) -109px -317px no-repeat; top: -10px; left: -5px; }
dd#monitorDef a:hover span{
display: block;
text-indent: 0;
vertical-align: top;
color: #000;
background-color: #F4F4F4;
font-weight: bold;
position: absolute;
border: 1px solid #BCBCBC;
bottom: 100%;
margin: 0;
padding: 5px;
width: 250%;
}
<dl id="officeMap">
<dt id="monitor">1. Monitor</dt>
<dd id="monitorDef"><a href="#"><span>Here's my 17" Monitor. I wish I had an LCD!</span></a></dd>
<dt id="phone">2. Phone</dt>
<dd id="phoneDef"><a href="#"><span>Does this thing ever stop ringing?</span></a></dd>
<dt id="case">3. PC Case</dt>
<dd id="caseDef"><a href="#"><span>This is my crazy Linux box! Gotta love that Linux...</span></a></dd>
<dt id="notebook">4. IBM ThinkPad</dt>
<dd id="notebookDef"><a href="#"><span>Here's my Linux notebook. Some crazy coding going on.</span></a></dd>
<dt id="floppy">5. External Floppy Drive</dt>
<dd id="floppyDef"><a href="#"><span>Floppy Drive. Ancient... I know!</span></a></dd>
</dl>