Support TailwindCSS 4.0

[itxshakil]

This PR introduces support for TailwindCSS 4.0 in the Laravel Breeze starter kit. It ensures compatibility with the latest version of TailwindCSS, offering improved utility classes, enhanced performance, and better developer experience.

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Changes:

1. Updated TailwindCSS Version:
   • Upgraded tailwindcss dependency to ^4.0.
   • Adjusted configuration files to match the new TailwindCSS 4.0 structure.
2. Configuration Adjustments:
   • Ensured compatibility with Laravel Mix and Vite, adapting build processes as needed.
   • Modified tailwind.config.js to align with updated syntax and features of TailwindCSS 4.0.
3. CSS and Component Updates:
   • Updated existing CSS classes in default views to avoid deprecated or removed utilities.
   • Verified and fixed any compatibility issues with new features, such as the removal of certain defaults or changes to class behaviors.

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References:

• [TailwindCSS 4.0 Upgrade Guide](https://tailwindcss.com/docs/upgrade-guide)

Please review and test the changes. Feedback and suggestions are welcome!

[Jubeki]

Similar to the skeleton PR: laravel/laravel#6523

How about replacing @tailwindcss/postcss with @tailwindcss/vite.

The app.css should also contain the source and the font-family.

[Jubeki]

In the InstallStack Files there is postcss listed, but I think it should be replaced with @tailwindcss/vite and the the vite.config.js should be adjusted accordingly.

autoprefixer can also be removed according to the upgrade guide:
https://tailwindcss.com/docs/upgrade-guide#using-postcss

[itxshakil]

In the InstallStack Files there is postcss listed, but I think it should be replaced with @tailwindcss/vite and the the vite.config.js should be adjusted accordingly.

autoprefixer can also be removed according to the upgrade guide: https://tailwindcss.com/docs/upgrade-guide#using-postcss

Thanks, I did the changes now

[Jubeki]

@itxshakil I think the problem with the tests is, that the postcss.config.js still exists on the laravel/laravel repository.

PR for Tailwind v4: laravel/laravel#6523

I think the only way to fix this, is to temporarily delete the postcss.config.js during the Tests run (Github Actions Workflow)

[Jubeki]

Or you can keep/add the following statement again:

$files->delete(base_path('postcss.config.js'))

[itxshakil]

Or you can keep/add the following statement again:

$files->delete(base_path('postcss.config.js'))

Thanks again.

[CharlieEtienne]

We should also replace ring black ring-opacity-5 with ring-black-5 in dropdown.
For example on line 34 in components/dropdown.blade.php