grid widths for different environments (mediatypes)

hello, it would be great if we could also specificy the width of a region for different media types. For example I may want my header to be 6/12 on normal but 12/12 on mobile displays.

Right now you can achieve this if you multiply all your regions/zones by 2 and then put the same blocks in them but make some visisble on normal and some on mobile. However this is a real pain.

What this would require is for the system to allow you to specify region widths per environment, and then when you hit save it would generate the various environment-css files with grid-width classes for the zones appropriate for the various media types/screen widths.

If there is interest in this I would be more than happy to collaborate with someone to help code this feature into the system. I can't promise I'd be able to put in a ton of hours per week, but I would certainly work to help add this into the gamut. My thinking is that it would extend the system much like Delta does with Context.

Thank you for a great system!