I've used it on a few projects successfully. The property ordering thing mentioned in other comments though is good to be aware of. It's not difficult to switch out for css nano if that is the case. The important feature for me was being able to target a browserlist string and flatten CSS nesting

Looks fine on my phone.

On my phone it has some extreme borders and in many lines it can only fit one single word.

It works fine for me--but I wonder if it has to do with the exessive shadow/glow effect?

TFA and GP are CSS minimizers - nothing to do with styles per se.