Adjustments to the fatnav and sidenav, and other CSS updates

chrome/common/extensions/docs/templates/articles/overview.html

 <h1>Overview</h1>
 
 
 <p>
 Once you've finished this page
 and the
 <a href="getstarted">Getting Started</a> tutorial,
 you'll be all set to start writing extensions.
 </p>
 
@@ skipping 492 matching lines @@
 
 
 <h3 id="chrome-more"> More details </h3>
 
 <p>
 For more information, see the
 <a href="api_index">chrome.* API docs</a>
 and watch this video:
 </p>
 
-<p>
-<iframe title="YouTube video player" width="640" height="390" src="http://www.youtube.com/embed/bmxr75CV36A?rel=0" frameborder="0" allowfullscreen></iframe>
-</p>
+<div class="video-container">
+  <iframe title="YouTube video player" width="640" height="390" src="//www.youtube.com/embed/bmxr75CV36A?rel=0" frameborder="0" allowfullscreen></iframe>
+</div>
 
 <h2 id="pageComm">Communication between pages </h2>
 
 <p>
 The HTML pages within an extension often need to communicate.
 
 Because all of an extension's pages
 execute in same process on the same thread,
 the pages can make direct function calls to each other.
 </p>
@@ skipping 76 matching lines @@
 <ul>
   <li> <a href="getstarted">Tutorial: Getting Started</a> </li>
   <li> <a href="tut_debugging">Tutorial: Debugging</a> </li>
   <li> <a href="devguide">Developer's Guide</a> </li>
   <li> <a href="samples">Samples</a> </li>
   <li> <a href="http://www.youtube.com/view_play_list?p=CA101D6A85FE9D4B">Videos</a>,
     such as
     <a href="http://www.youtube.com/watch?v=B4M_a7xejYI&feature=PlayList&p=CA101D6A85FE9D4B&index=6">Extension Message Passing</a>
     </li>
 </ul>