title: Yii2 NavBar - which property to add class to navbar-header?
body: <p>I've included some of the default Yii2 output below for reference.</p>
  
  <pre><code>&lt;nav id="w0" class="navbar-inverse navbar-fixed-top navbar" role="navigation"&gt;
      &lt;div class="container"&gt;
          &lt;div class="navbar-header"&gt;
         ...
  </code></pre>
  
  <p>The code I have is...</p>
  
  <pre><code>NavBar::begin([
      'options' =&gt; [
          'class' =&gt; 'navbar navbar-default navbar-custom navbar-fixed-top',
      ],
      'brandOptions'=&gt;[
          'class'=&gt;'page-scroll'
      ],
      ...
  ]);
  </code></pre>
  
  <p>which outputs...</p>
  
  <pre><code>&lt;nav id="w0" class="navbar navbar-default navbar-custom navbar-fixed-top" role="navigation"&gt;
      &lt;div class="container"&gt;
         &lt;div class="navbar-header"&gt;
         ...
  </code></pre>
  
  <p>The <code>brandOptions</code> are applied, as desired, to the brand link later in the output. The output I'm seeking is...</p>
  
  <pre><code>&lt;nav id="w0" class="navbar navbar-default navbar-custom navbar-fixed-top" role="navigation"&gt;
      &lt;div class="container"&gt;
         &lt;div class="navbar-header page-scroll"&gt;
         ...
  </code></pre>
  
  <p>I'm wanting to add a class to the 2nd div there, the one that gets "navbar-header" but for all my attempts I haven't been able to identify the property to apply it on. Any tips?</p>
  
  <p>Thanks in advance,
  Pedro :)</p>