Custom Crit and Fumble borders for a multiple dice roll total

I'm making my own character sheet stuff for a campaign I'll run at some point hopefully. I've gotten so far as to be writing the dice roll macros now, but I'm uncertain on how to proceed. In the system this is all for, the core roll is 2d6, where a 2 is a crit success and a 12 is a crit fail. I was wondering how I should go about doing this since it seems you can't use cs and cf on raw numbers or grouped rolls.

It sounds like the new matching mechanic that is being rolled out would work for you. Not sure how it's going to be represented in the css of the inline roll, or how it will display (show the actual roll or show 0/1 like the success/failure).