I created one grid system exactly like this [1] a couple of years ago as part of Picnic CSS [2].
However it was limiting in several factors, so I rewrote it from scratch as a flexbox solution, called it Flexpoint [3] and I love it. Now I need to integrate it back into Picnic.
For instance, can you change elements order? How do you account for an undetermined number of elements (same size, full width total)?
[1] http://web.archive.org/web/20150713011953/http://www.picnics...