Can't see zero blocks on black Emacs background

[Google Code Exporter]

What steps will reproduce the problem?
1. Customize Emacs background color to black
2. Play bintris

What is the expected output? What do you see instead?

I don't see the zero (black) blocks as they're the same color as the
background.

A proposed fix for this is to use default text-color for the blocks and
just make them `0` or `1` chars instead of blocks.  I'm not sure how to
easily do this with the `gamegrid.el` library that comes with Emacs.

Thanks _boredzo_ for reporting it.

Original issue reported on code.google.com by [e-mail] on 16 Sep 2007 at 7:26