Roman Dvornov

Could you please provide more details, why white spaces need to be retained in these cases? As I know white spaces inside a function is not required. The single exception...

CSSO does it best to make such transformations. However, this optimisation works for limited list of shorthands, i.e. `padding` and `margin` is supported, but `font` is not. Current output (CSSO...

CSSO doesn't merge declarations in this case because of > to avoid breaking the fallback for browsers not supporting rgba On the one hand, browsers that doesn't support for `rgba()`...

Duplicate #143

@ygoe Which version of CSSO do you use? CSSO recognises `:where()` selector and calculates its specificity right starting `5.0`.

Initial comment looks the same as #143

Issue is about `background` property only, see [explanation in related issue](https://github.com/css/csso/issues/330#issuecomment-290977696) (#330). It would be fixed in the future.

The is not about property priority. `CSSO` doesn't merge background property values or override them due of the complexity of that property (various browser support, complex merge model, many edge...

Which version of CSSO do you use? Can't reproduce in the latest version: 

@nabtron That's correct behaviour. Suppose we have a markup: ```html text ``` Ans styles from your example: ```css .a1 { color: red } .a2 { color: green } .b1 {...