Changing caption size

I’m using the tropicala theme on my wordpress (ver. 2.7) site and am trying to enlarge the caption text for the thumbnail images (www.mcaddengroup.com/home-delete).

I have been messing around with the code in my style.css but it doesn’t have any affect on the captions for the thumbnails.

/* Image stuff for 2.6.1 */
.aligncenter {
  display: block;
  margin-left: auto;
  margin-right: auto;
}

.alignleft {
  float: left;
}

.alignright {
  float: right;
}

.wp-caption {
  border: 1px solid #ddd;
  text-align: center;
  background-color: #f3f3f3;
  padding-top: 4px;
  margin: 10px;
  -moz-border-radius: 3px;
  -khtml-border-radius: 3px;
  -webkit-border-radius: 3px;
  border-radius: 3px;
}

.wp-caption img {
  margin: 0;
  padding: 0;
  border: 0 none;
}

.wp-caption-dd {
  font-size: 11px;
  line-height: 17px;
  padding: 0 4px 5px;
  margin: 0;
}

p.entry_info {
  clear:both;
}

div.navigation {
  margin:10px 0;
}

My goal is to have three image buttons with a question under each one (i.e. What is a loan modification?). I tried to do a fast and cheap approach by just placing simple text over the buttons in the visual editor but the questions are too long to fit cleanly on top.

Any ideas? …Bueller? …Bueller?