Question

I have two floating divs.
I would like the first div to be 100px wide and the other div’s width to be the rest. Something like:

<div style="float:right;width:100px;height:100px;background:black;"></div>
<div style="float:left;width:100%;height:100px;background:yellow;"></div>

Here is jsfiddle.

There is one rule: I don’t know the width of the page!

Answer 1

If you take the float:left;width:100%; off the second div, it should work the way you want it. When a block is floated to the right, the non-floated objects flow around it. Since you’ve set the height to be the same for the two blocks, they will line up nicely.

I’ve updated your jsfiddle to show how this works.