Expand a div to fill the remaining width

Question

I want a two-column div layout, where each one can have variable width e.g.

Answer 1

I don't understand why people are willing to work so hard to find a pure-CSS solution for simple columnar layouts that are SO EASY using the old TABLE tag.

All Browsers still have the table layout logic... Call me a dinosaur perhaps, but I say let it help you.

  

    
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Much less risky in terms of cross-browser compatibility too.