Strawberry is a new flexbox based CSS micro-framework, a set of common flexbox’s utilities focused on making life easier and faster with nested flexboxes. You can easily create nested flexboxes directly from the container. So it can also considered like a fallback for CSS Grid.
Some good points of it:
I started this project on June 5th 2018, it is written in SASS and it could be installed using node, forking the repo or using the CDN.
Here github repo: https://github.com/jfet97/strawberry