title: Why does the width of affix column change while scrolling in Bootstrap?
body: <p>In Bootstrap I made two columns one with affix to make it fixed while scrolling and one normal column.
  Here is the <a href="http://jsfiddle.net/4zuo6dm7/2/" rel="nofollow">demo</a></p>
  
  <p>This is my code so far:</p>
  
  <pre><code>&lt;body data-spy="scroll" data-target="#myScrollspy"&gt;
  &lt;div class="container"&gt;
      &lt;div class="row"&gt;
          &lt;div class="col-md-3" id="myScrollspy"&gt;
              &lt;div class="panel panel-default" data-spy="affix" data-offset-top="0"&gt;
                  &lt;div class="panel-body"&gt;Lorem ipsum&lt;/div&gt;
              &lt;/div&gt;
          &lt;/div&gt;
          &lt;div class="col-md-9"&gt;
              &lt;div class="panel panel-default"&gt;
                  &lt;div class="panel-body"&gt;
                      &lt;p&gt;Lorem ipsum &lt;/p&gt;
                  &lt;/div&gt;
              &lt;/div&gt;
          &lt;/div&gt;
      &lt;/div&gt;
  &lt;/div&gt;
  &lt;/body&gt;
  </code></pre>
  
  <p>If you check the demo, as soon as you scroll down, the width of the small column which has affix changes. Why is that?</p>
  
  <p>Is there any idea to fix it?
  Thanks </p>