title: CSS Accordion Nav - Need default tree open IF no others are open
body: <p>I made a navigation bar essentially using this guide:</p>
  
  <p><a href="http://designshack.net/articles/css/verticalaccordionav/" rel="nofollow">http://designshack.net/articles/css/verticalaccordionav/</a></p>
  
  <p>What I need is for one default tree (header + sub-links) to be expanded upon page load, which I know I can do by declaring the height to that section in the CSS. The problem is, I only want it to stay expanded IF no other trees are expanded i.e. no other categories are hovered over. Basically: only 1 tree should be expanded at a time, but I'd like when no trees are being hovered over for the default to be the expanded tree.</p>
  
  <p>Any way to do this? CSS-only solution is preferred, but I have a feeling this requires if/then statements and thus can't be done with CSS.</p>