sizing utilities using --spacing variables instead of --container

[marcospgp]

What version of Tailwind CSS are you using?

"^4.1.7",

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

bun 1.2.13+64ed68c9e

What version of Node.js are you using?

bun 1.2.13+64ed68c9e

What browser are you using?

Chrome

What operating system are you using?

windows

Reproduction URL

n/a

Describe your issue

using utilities like size-xl or max-w-md should rely on sizing variables with the --container prefix as per docs (such as --container-xl), but they instead use --spacing variables

[wongjn]

Consider seeing previous maintainer responses on this topic:

• Bug: max-w uses --spacing instead of --container #17777 (comment)
• max width uses spacing variables instead of container #18043 (comment)

Though I don't think it makes sense for size-* to read from --container. --container is more for horizontal sizings for site-width-constraining utilities/conditions, like max-w-* and container queries. Since size-* sets both height and width, it feels like a more general sizing utility.

[marcospgp]

this only seems to happen if I have defined custom --spacing variables in my CSS tailwind @theme config!

so if I use basis-5xl or similar and have a matching --spacing-5xl in my theme config, it will match. if I don't, it will correctly fall back to the --container predefined theme variable.

IMO not expected behavior