no-unknown-class

Engine-powered: when the linted repo has Tailwind installed, dscheck compiles each class through Tailwind itself. A class that produces no CSS is fabricated — the class-level version of a hallucinated token — and gets a did-you-mean from your theme:

✖ Unknown class bg-brnad — did you mean bg-brand?

• Requires: Tailwind v4 installed in the linted project (otherwise the rule is silent — dscheck never guesses class validity from patterns alone).
• Default severity: error — like no-unknown-token, there is no legitimate steady state.
• Not flagged: anything when the engine is unavailable (the rule goes silent, never approximate), classes containing arbitrary values (those go to the value rules).
• Variants are preserved in suggestions (md:bg-brnad → md:bg-brand).