title: Change active Bootstrap menu item using html and css
body: <p>I want to be able to change which menu item in is active depending on which file I am in. I include menu.html (the file below) in my three files: a.html, b.html and c.html.
  How can I do this using only html and css? I use the Boostrap menu.
  I basically want to change the menu item which is active according to the current file I am in.</p>
  
  <pre><code>&lt;ul id="navbar_menu" class="nav nav-tabs nav-justified"&gt;
              &lt;li id="a"&gt;&lt;a href="#"&gt;a&lt;/a&gt;&lt;/li&gt;
              &lt;li id="b"&gt;&lt;a href="#"&gt;b&lt;/a&gt;&lt;/li&gt;
              &lt;li id="c"&gt;&lt;a href="#"&gt;c&lt;/a&gt;&lt;/li&gt;   
          &lt;/ul&gt;
  </code></pre>