[Bug?]: cssChunking / CSS Optimisations - Module CSS getting reset by tailwind's global styles

[rohitpotato]

Link to the code that reproduces this issue

https://github.com/GabenGar/repros/blob/main/nextjs/css-out-of-order/README.md

To Reproduce

1. Upgrade to NextJs version 14.2.5
2. Build prod
3. Write some CSS inside a .module.css file.
4. See the changes

Current vs. Expected behavior

Tailwind CSS's preflight styles overwrite Tailwind CSS written inside module CSS.

Example:

button.module.css

.button {
 @apply bg-red-500;
}

Expected Behaviour: Button color is red.

Current Behaviour: Button color is transparent since module CSS is overwritten by tailwind's preflight styles.

Provide environment information

Relevant packages:

Next - 14.2.5

Which area(s) are affected? (Select all that apply)

Not sure, create-next-app, Navigation

Which stage(s) are affected? (Select all that apply)

next build (local), Other (Deployed)

Additional context

We have a big legacy project where we have written tailwind classes inside module CSS by using the apply directive. At some places, these styles are being reset by Tailwind's preflight styles. This started happening after the next JS upgrade to version 14.2.5 and we are unable to move further.

I have tried the cssChunking as per the documentation but that is having no effect.

Is there any workaround? Rewriting everything back to tailwind classes is a very bandwidth heavy task for our team.

[alexanderbira]

This is related to #64921

[github-actions]

We cannot easily recreate the issue with the provided information. Please add a minimal reproduction in order for us to be able to help more efficiently.

Why was this issue marked with the please simplify reproduction label?

There was a reproduction provided, but due to its complexity, we cannot easily reproduce the issue.

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Anyone experiencing the same issue is welcome to provide a minimal reproduction following the above steps.

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[samcx]

@rohitpotato If we can get a simpler outside of your , that will be great!

[rohitpotato]

@samcx its a private repo, i cant really share the code. But the above sandbox is as simple as it gets. Please check with this if possible.

[samcx]

@rohitpotato I'm afraid there is way too much going on in that repository for us to dig into.

Ideally, a would only contain your Layout + Page, your tailwind global styles, and the module.css for the Page.

Are you intermixing Client and Server components? That might be part of the issue.

[balazsorban44]

This issue has been automatically closed because it received no activity for a month and had no reproduction to investigate. If you think it was closed by accident, please leave a comment. If you are running into a similar issue, please open a new issue with a reproduction. Thank you.

[github-actions]

This closed issue has been automatically locked because it had no new activity for 2 weeks. If you are running into a similar issue, please create a new issue with the steps to reproduce. Thank you.