CSS styles not working…?

I am working on my blog and for some reason it is not reading the CSS styles that I have on things. The blog is at http://www.babybumps.net/blog

For example… at the bottom of the page there is a navigation section. I have the styles set to make the headers be different colors. However, right now they are just showing as a dark grey.

Here is the code for my footer.php file:

<!-- Begin Footer -->
<div id="footer-wrap">
 <div id="footer">

<br /><br />
 <img src="http://www.babybumps.net/images/bottom-colorbar.gif" alt="" width="800" height="22" />
  <br />

  <table width="790" border="0">
    <tr>

      <th><img src="http://www.babybumps.net/images/spacer.gif" alt="" width="150" height="1" />      </th>

      <th valign="top"><div id="ad_header">Advertisers</div>
          <ul>
            <li><a href="http://www.babybumps.net/packet.pdf">Sales Info (pdf)</a></li>
            <li><a href="http://www.babybumps.net/contact.html">Contact Sales</a></li>
            <li><a href="http://www.babybumps.net/banners.html">Link to us</a></li>
          </ul>        </th>

      <th valign="top"><div id="events_header">Local Events </div>
          <ul>
            <li><a href="http://www.babybumps.net/calendar.php">Calendar</a></li>
            <li><a href="http://www.babybumps.net/contact.html">Add your event </a></li>
          </ul>          </th>

      <th valign="top"> <div id="info_header">More Info </div>
          <ul>
              <li><a href="http://www.babybumps.net/contact.html">Contact Us </a></li>
              <li><a href="http://www.babybumps.net/contact.html">Suggestions? </a></li>
            </ul>          </th>
    </tr>
  </table>

  <br /><br />

      <a href="http://www.babybumps.net/welcome.html">Welcome to BabyBumps.net</a> | <a href="http://www.babybumps.net/terms.html">Terms of Use</a> | <a href="http://www.babybumps.net/banners.html">Link to Us</a> <br />
      <strong>BabyBumps.net Copyright &copy; 2007 BabyBumps.net LLC</strong> <br />
    </div>
</div>
</div>
</body>

</html>

and here are the CSS rules I am using for that section:

.ad_header {
	color: #FF7461;
	font-family: Geneva, Arial, Helvetica, sans-serif;
	font-size: 16px;
	font-weight: bold;
}
.events_header {
	font-family: Geneva, Arial, Helvetica, sans-serif;
	font-size: 16px;
	font-weight: bold;
	color: #14BAA6;
}
.info_header {
	font-family: Geneva, Arial, Helvetica, sans-serif;
	font-size: 16px;
	font-weight: bolder;
	color: #9CB04D;
}

Does anyone know why it isn’t working? I may be writing the CSS styles wrong, but if I am I am totally lost…