title: Make DIV fill remainder of page vertically?
body: <p>I have a Google Maps app that takes up most of the page.  However, I need to reserve the top-most strip of space for a menu bar.  How can make the map div automatically fill its vertical space?  <code>height: 100%</code> does not work because the top bar will then push the map past the bottom of the page.</p>
  
  <pre><code>+--------------------------------+
  |      top bar  (n units tall)   |
  |================================|
  |              ^                 |
  |              |                 |
  |             div                |
  |     (100%-n units tall)        |
  |              |                 |
  |              v                 |
  +--------------------------------+
  </code></pre>