Background-color behind a border-radius
<p>I was wondering, is it possible to set a background-color behind the border-radius?</p>

<p>I want to achieve this effect:
<a href="https://i.stack.imgur.com/NAZvf.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/NAZvf.png" alt="enter image description here"></a></p>

<p>I use this HTML:</p>

<pre><code>&lt;div class="content-header" tabindex="-1"&gt;
    &lt;span class="html"&gt;TITLE&lt;/span&gt;
&lt;/div&gt;
&lt;div class="content-txt-v2" tabindex="-1"&gt;
  &lt;p&gt;
  Content
  &lt;/p&gt;        
&lt;/div&gt;
</code></pre>

<p>and I use this CSS:</p>

<pre><code>.content-header {
    height: 18px;
    line-height: 18px;
    background-color: #4C741B;
    margin-top: 20px;
    float: left;
    -moz-border-radius: 10px 10px 0px 0px;
    -webkit-border-radius: 10px 10px 0px 0px;
    -khtml-border-radius: 10px 10px 0px 0px;
    border-radius: 10px 10px 0px 0px;    
    padding: 0px 14px;
    font-weight: bold;
    font-size: 14px;
    color:#fff;
}
.content-txt-v2 {
    clear: both;
    width: 669px;
    padding: 0 10px;
    margin: 0px auto;
      border: 2px solid #E9EAE3;
    -moz-border-radius: 20px 10px 10px 10px;
    -webkit-border-radius: 20px 10px 10px 10px;
    -khtml-border-radius: 20px 10px 10px 10px;
    border-radius: 20px 10px 10px 10px;
    float:left;
    background-color:red;
}
</code></pre>

<p>I added the above code in a <a href="https://jsfiddle.net/85c8ss94/" rel="nofollow noreferrer">JSFIDDLE</a></p>

<p>I tried to set the background-color of my content-txt-v2 div but with no succes. Can anyone guide me in the right direction? Is it possible with only two div's? or should I add more objects?</p>