[csswg-drafts] [css-values] Re-adding min() and max()?

LeaVerou has just created a new issue for 
https://github.com/w3c/csswg-drafts:

== [css-values] Re-adding min() and max()? ==
Perhaps now that Values 3 has gone to CR it's time to reconsider 
adding `min()` and `max()` back into Values 4?

Authors are doing extremely 
[weird](http://blog.typekit.com/2016/08/17/flexible-typography-with-css-locks)
 [hacks](http://fvsch.com/code/css-locks/) with `calc()` to emulate 
them in `font-size` and `line-height`, which they call "CSS locks". If
 you google _CSS locks_ you will see how widespread these hacks are 
becoming, indicating a clear author need.

Furthermore, as CSS variables become more widely used, the need for 
`min()` and `max()` will become even greater. I recall some of the 
issues that [made us drop them 6 years 
ago](https://lists.w3.org/Archives/Public/www-style/2010Sep/0233.html)
 can now be solved with the _invalid at computed value time_ concept 
that Variables introduced.

Please view or discuss this issue at 
https://github.com/w3c/csswg-drafts/issues/544 using your GitHub 
account