Are em's supported?

[ianobermiller]

The readme was a bit confusing on this point; the example uses ems, but the docs say that ems are not supported.

[alexlande]

I believe ems aren't supported for line-height (the idea being that you should use unit-less line-height, but all units are supported for font-size.

(right, @tptee?)

[tptee]

That's correct, thanks @alexlande!

I'll update the docs soon!