Advanced CSS Layout | Fixed Column w/ Very Large Picture

OK so my brain is just probably not working tonight. What I'm trying to accomplish is a two column layout where one column scrolls and the other is fixed. The fixed column has a very large background image in it that I would like to be able to scale to the size of the screen. Additionally the left (fixed) column's width would have to scale to accommodate the background image. The best way to really explain this is with a picture:

The highlighted area with the arrow in it will scroll and the other column with the picture and twitter status in it would remain fixed. My problem does not come into play with the fixed CSS positioning. My issue is with scaling my columns based on screen size so that the picture always remains in the proportion it's shown here both in it's own dimensions and those of the other colu开发者_C百科mn. That's what I'm stuck on. Any ideas? I really appreciate the help.

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I think you can just use an image element in your first column and set it to take 100% of its parent. If the parent div is also a percentage then its size will change of course and that also scales the image within. If we want the image to scale, then we can't also specify a height.

<div id="parent" style="width: 40%">
  <img id="child" style="width: 100%" src="http://i.stack.imgur.com/lvvrv.png" alt="Fake Background" />
</div>

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Check your JS FIDDLE CODE HERE : http://jsfiddle.net/4P9fJ/7/

Since you din't mention you'd be changing the images in your background i provided the background image in the body tag .