title: How to add css class to an element inside nav element
body: <p>I have a <code>&lt;nav&gt;</code> element on my page that contains couple of <code>&lt;div&gt;</code> elements and one of the divs contains a number of images. I want to add a border to the images so I have added a class to the css file:</p>
  
  <pre><code>.img-cls
  {
       border: solid blue 1px;
  }
  </code></pre>
  
  <p>Now if I add <code>class="img-cls"</code> to any image on the page, it adds a border, but if I add the same to any image inside <code>&lt;nav&gt;</code>, nothing changes. Can anyone help me fix the issue?</p>
  
  <p>Below is my html:</p>
  
  <pre><code>&lt;form id="form1" runat="server" method="post"&gt;
      &lt;nav class="navbar navbar-default navbar-fixed-top"
           role="navigation"&gt;
  
          &lt;div id="divContainer" class="container"&gt;
              &lt;div class="navbar-header"&gt;
  
              &lt;/div&gt;
              &lt;div id="navbarContent" class="collapse navbar-collapse"&gt;
  
              &lt;/div&gt;
  
              &lt;div&gt;
                  &lt;div class="input-group"&gt;
                      &lt;span class="input-group-addon"&gt;ID&lt;/span&gt;
                      &lt;input type="text" id="txtID" class="form-control"
                             placeholder="Enter your id here" /&gt;
                  &lt;/div&gt;
                  &lt;br /&gt;
                  &lt;button type="submit" class="btn btn-primary btn-lg btn-block"&gt;
                      Submit Data
                  &lt;/button&gt;
                  &lt;br /&gt;
                      &lt;img src="images/DOS.png" class="img-cls"/&gt;
                      &lt;img src="images/SR.png" class="img-cls"  /&gt;
                      &lt;img src="images/RFI.jpg" class="img-cls"  /&gt;
              &lt;/div&gt;
  
  
          &lt;/div&gt;
      &lt;/nav&gt;
  
  &lt;/form&gt;
  </code></pre>