[big_paps]

Well this looks like something useful. Can't imaging how much work is needed to first understand css and then to build a layout engine around it.

[troupo]

There's also Facebook's Yoga: https://github.com/facebook/yoga

[Rohansi]

Yoga is great but only really supports flexbox. For most cases that can be enough but inline content (as shown in the Dropflow demo) is difficult with only flexbox layouts available.