!z-40 not working in Tailwind CSS v4

[Navidtm]

What version of Tailwind CSS are you using?

v4.0.8

What build tool (or framework if it abstracts the build tool) are you using?

tailwind play

What browser are you using?

Chrome

What operating system are you using?

Linux

Reproduction URL

https://play.tailwindcss.com/QP00crgkmX

Describe your issue

Using !z-40 in Tailwind CSS v4 does not apply the expected

Expected

.\!z-40 {
  z-index: 40 !important;
}

Actual

.\!z-40 {
  z-index: 40;
}

Even testing in Tailwind Play does not produce the correct result.

[philipp-spiess]

Thanks for catching! Will be fixed with the next patch!