Div wont extend to bottom of its contents when divs inside it are floated
<p>I have 2 divs as columns, both are floated left and set to clear none. Their container div has a background image at the top, so the background is at the top of both columns.</p>

<p>I want to be able to also have a background image at the bottom of the columns. I've created another div which sits inside the container div (but outside the columns) and set a background image to its bottom.</p>

<p>The problem is that this div doesn't extend to the bottom of the columns it contains. How can I make it do this? I've tried playing around with floats and clearing but without any luck.</p>
