Bug: `no-invalid-properties` ignores invalid declarations inside nested at-rules

[xbinaryx]

Environment

ESLint version: 9.39.2
@eslint/css version: 0.14.1
Node version: 24.13.0
npm version: 11.6.2
Operating System: Win11

Which language are you using?

stylesheet

What did you do?

Configuration

<!-- Paste your configuration here -->

.responsive {
  width: red;

  @media (max-width: 800px) {
    width: red;
  }
}

What did you expect to happen?

All invalid declarations (width: red) should be reported as errors, including those inside nested at-rules.

Per the CSS Nesting spec, declarations inside nested at-rules are valid CSS and behave as if they were wrapped in an implicit & {} block, so they should be linted the same way as top-level declarations.

What actually happened?

Only the top-level width: red; declaration is reported.

Link to Minimal Reproducible Example

N/A

Participation

• I am willing to submit a pull request for this issue.

Additional comments

https://developer.mozilla.org/en-US/docs/Web/CSS/Guides/Nesting/At-rules

[nzakas]

Totally agree, this is a bug. Marking as accepted.

[eslint-github-bot]

👋 Hi! This issue is being addressed in pull request #369. Thanks, @xbinaryx!