Change background with jQuery addClass
<p>I'm trying to change the background color by adding a new class with another background color. But the color don't change. It's still the same color! Do I have to remove the old background color first? I guess my code should work!?</p>

<pre><code>$(".displayControl a:first").addClass("activeButton");
</code></pre>

<p>The css</p>

<pre><code>.displayControl
{
padding: 20px 0 0 0;
float: right;
}

.displayControl a
{
background: #B7BABD;
margin: 0 5px 0 0;
padding: 5px 10px 5px 10px;
color: #ffffff;
}

.activeButton
{
background: #83AEE6;
}
</code></pre>
