I wonder if some of you used Blocs. It’s based on Bootstrap like Concrete CMS and think it would be so great to be able to design pages from Blocs to Concrete CMS.
As I’m not a developer I have no idea about how hard it would be to make those 2 compatible.
If the result is a HTML page ideally with a separate stylesheet (css) it is possible to build a theme from it.
Maybe you should check the license for copyright issues, but technically it is possible.