How to force Dojo TitlePane to overlap with CSS?
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I have this [jsfiddle][1] which has two `TitlePane` widgets in the top right of the center pane.  Right now, when the right `TitlePane` ("Switch Basemap") is clicked, it causes the left `TitlePane` ("Map Overlays") to shift to the left.  Instead, I would like for the right `TitlePane`, when opened, to hide the left `TitlePane` rather than shift it.

I have tried playing with `z-index`, `overflow`, `position`, and `float`, but no luck so far.  I am fairly new to Dojo so I think I haven't found the correct combination of style parameters.

Does anyone have any ideas?

Thanks in advance!

  [1]: http://jsfiddle.net/fugKS/