There's a new CSSGrid release 0.9.1 with lots of improvements!
Here's a sample using justify and alignment along with auto-flow algorithm in CSS Grid. The left and right most nodes are fixed in place, while the rest of the nodes are positioned dynamically. The second row of elements adjust their justify or align properties.

It's a pretty big update:
- basic html/css style layout for non-grid nodes using computeLayout taken from Figuro
- basic html layout using constraints like percent parent (20'pp), auto (cx"auto"), content-min (cx"content-min")
- support for constraint operators including min, max, - and + (limited to single level, e.g. no min(min(x,y),z))
- basic and grid layouts now support min-size and max-size constraints (e.g. like CSS min-width)
- fixed justify and align bugs and gotchas for CSS Grids
- lots more test coverage
- the core UiScalar type is configurable to support float32, float64, int, int32, int64 by using a compile flag (great for embedded or terminal projects!)
I haven't created much documentation yet. Though the tests provide pretty good examples. Next I may add support for padding and margins, but haven't decided yet.