Is it possible to reference the nav bar (and footer) in the CSS in order to make faster site-wide changes to the navigation?

For example, if I wanted to add a new page (and associated drop-down menu item) I would have to add the code to every page.

http://www.diamondpackaging.com/green/
http://www.diamondpackaging.com/green/diamond.css

Thanks

What would be more expedient is to use Server-side includes.

Agreed... It's been a bit since I've done it but this should work for you. Make a file, for example, navmenu.html and put this in it:

<!-- start nav -->
  <div id="nav">

    <ul>
	<li> <a href="about/index.htm" title="about" onmouseover="dropdownmenu(this, event, 'anylinkmenu1')">about</a></li><li>|</li>
	
	             <div style="visibility: visible; left: 85px; top: 183px;" id="anylinkmenu1" class="anylinkcss">

                 <a href="about/news.htm">news</a>
                 <a href="about/casestudies.htm">case studies</a>
                 <a href="about/affiliations.htm">affiliations</a>

                 
                 </div>
	
	<li><a href="sustainability/index.htm" title="sustainability" onmouseover="dropdownmenu(this, event, 'anylinkmenu2')">sustainability</a></li><li>|</li>
	
	
	             <div style="visibility: hidden; left: 191px; top: 183px;" id="anylinkmenu2" class="anylinkcss">

                 <a href="sustainability/movement.htm">movement</a>
				 <a href="sustainability/packaging.htm">packaging</a>
                 <a href="sustainability/cradle.htm">cradle to cradle</a>

                 
                 </div>
		
	
	<li><a href="designs/index.htm" title="designs" onmouseover="dropdownmenu(this, event, 'anylinkmenu3')">designs</a></li><li>|</li>
	
	 			 <div style="visibility: hidden; left: 348px; top: 183px;" id="anylinkmenu3" class="anylinkcss">

                 <a href="designs/cad.htm">cad</a>
                 <a href="designs/scorecard.htm">scorecard</a>
                 
                 </div>

		
	
	<li><a href="materials/index.htm" title="materials" onmouseover="dropdownmenu(this, event, 'anylinkmenu4')">materials</a></li><li>|</li>
	
	             <div style="visibility: hidden; left: 467px; top: 183px;" id="anylinkmenu4" class="anylinkcss">

                 <a href="materials/paper.htm">paper</a>
                 <a href="materials/plastic.htm">plastic</a>
				 <a href="materials/inks.htm">inks/coatings</a>
                 
                 </div>

		
	
	<li><a href="methods/index.htm" title="methods" onmouseover="dropdownmenu(this, event, 'anylinkmenu5')">methods</a></li><li>|</li>
	
	             <div style="visibility: hidden; left: 598px; top: 183px;" id="anylinkmenu5" class="anylinkcss">

                 <a href="methods/recycling.htm">recycling</a>
                 <a href="methods/efficiency.htm">efficiency</a>
				 <a href="methods/management.htm">management</a>
                 
                 </div>

	
	<li><a href="wind/index.htm" title="wind energy" onmouseover="dropdownmenu(this, event, 'anylinkmenu6')">wind energy</a></li><li>|</li>
	
	             <div style="visibility: hidden; left: 723px; top: 183px;" id="anylinkmenu6" class="anylinkcss">

                 <a href="wind/about.htm">about</a>
                 <a href="wind/faq.htm">FAQs</a>
				 <a href="wind/rec.htm">RECs</a>
				 <a href="wind/epa.htm">EPA</a>

                 
                 </div>
	
	
	<li><a href="educate/index.htm" title="educate" onmouseover="dropdownmenu(this, event, 'anylinkmenu7')">educate</a></li>
	
		         <div style="visibility: hidden; left: 872px; top: 183px;" id="anylinkmenu7" class="anylinkcss">

                 <a href="educate/definitions.htm">definitions</a>
                 <a href="educate/acronyms.htm">acronyms</a>
				 <a href="educate/articles.htm">articles</a>

				 <a href="educate/links.htm">links</a>
				 <a href="educate/videos.htm">videos</a>
				 <a href="educate/calculator.htm">calculator</a>
                 
                 </div>
		
	</ul>
  </div>
  <!-- end nav -->

Then, anywhere you want to reference that menu you, put in your page <?php include('navmenu.html'); ?> and that will insert the other HTML text.

Keep in mind though that you will be executing PHP code and therefore you should rename the file that contains the include(); statement to pagename.php so that the server knows there is php to parse in the file.

i've used this method for a while now and it really saves you some time.

just set up the information in the css, and it will work perfectly for you.