Lower CSS specificity by wrapping styles in @layer

[felix-bohlin]

Description

Lowers CSS specificity by wrapping the styles in @layer. In my project (a component library) I'd like a lot of control over the styles and this solution would make it easier to override some of the Starlight styles.

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Latest commit: 449b6ec

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[delucis]

Thanks for the PR @felix-bohlin. We already have a PR for this that we’re working on so will close this as a duplicate of #2322.