docs: theme generator css modal color issue

[cancakar35]

On which page do you see this issue?

https://daisyui.com/theme-generator

Describe the issue

Text in css view modal is unreadable in light themes.

I think this line causes the issue: https://github.com/saadeghi/daisyui/blob/master/packages/docs/src/components/themegenerator/ThemeCSSModal.svelte#L116

What browsers are you seeing the problem on?

Chrome, Edge, Chrome Android

[github-actions]

Thank you @cancakar35 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.