Use dashed idents in our examples of custom constructs

[jeddy3]

Clearly describe the documentation issue

We should use dashed idents in our examples of custom constructs to align with the specs (see example 7), e.g. @--custom rather than @custom.

This is in line with Stylelint's emphasis on standard CSS in our rules and docs.

Ref: #5520 (comment)

• At-rules
• Functions
• Units
• Selectors

[sylwia-lask]

Hi @jeddy3, I think I can do that next week, but please tell me should I branch off v14 or master?

[hudochenkov]

Use v14, please.

…

On Sun, Sep 19, 2021 at 15:10 Sylwia Laskowska ***@***.***> wrote: Hi @jeddy3 <https://github.com/jeddy3>, I think I can do that next week, but please tell me should I branch off v14 or master? — You are receiving this because you are subscribed to this thread. Reply to this email directly, view it on GitHub <#5523 (comment)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/AAE72BLYKUNZZWFVYS5MGG3UCXOMPANCNFSM5D4BMB6A> .

[ybiquitous]

I believe we've rewritten all the examples. If there is what we missed, please let us know or open a pull request.