bug: Lack of contrast between in button foreground and background colors for join items

[nbran]

What version of daisyUI are you using?

v5.0.0

Which browsers are you seeing the problem on?

All browsers

Reproduction URL

https://play.tailwindcss.com/6KeZsulsMW

Describe your issue

The values computed for --btn-bg and --btn-fg don't seem appropriate when buttons are used as join items.

[github-actions]

Thank you @nbran for reporting issues. It helps daisyUI a lot 💚
I'll be working on issues one by one. I will help with this one as soon as a I find a solution.
In the meantime providing more details and reproduction links would be helpful.