Facebox Terms of Service popup on Phones - doesn't fit screen

[gsullins]

The Facebox Terms of Service modal popup, which happens when TOS is clicked into, at the bottom of the checkout page, is too big for phones, since it's using fixed pixel width.  I'm adjusting via facebox css, and using Firebug, but can't quite work out how to resize the popup window to be perhaps a % of screen size, versus fixed pixels.  Help is greatly appreciated.

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