What version of Tailwind CSS are you using?

For example: v4

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

For example: vite

What version of Node.js are you using?

For example: v23

What browser are you using?

For example: Chrome

What operating system are you using?

For example: Linux

Describe your issue

I mainly using tailwindcss to structure my layout (utilities), I've successfuly migrated from v3 to v4.
But there is a small issue, using @import 'tailwindcss'; works but --spacing is missing a default.

which makes all properties relying on this variable broken.