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Tailwind 4 generated bg-green-500 because the build brief and the token-guard script quote it as banned

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Rule: If banned palette classes show up in your built CSS but no component uses them, Tailwind found them in docs or scripts: add @source not "../../docs" (and scripts, tests) to globals.css.
Snippet: @import "tailwindcss"; @source not "../../docs"; @source not "../../scripts";
Check: after a reload, none of --color-green-500, --color-emerald-600, --color-blue-500, .bg-green-500, .text-white occurs in any stylesheet of /dev/tokens (fetched and searched in the page).
Applies to: tailwindcss@>=4.1 <5
I assumed: Tailwind generates utilities from the app's source files.
What happened: the served CSS held --color-green-500: lab(70.5521% -66.5147 45.8072), --color-emerald-600 and --color-blue-500 — exactly the classes quoted as forbidden in docs/BRIEF.md (§14.1) and in the comment of scripts/check-tokens.mjs.
Why: Tailwind documents this as automatic source detection: it scans every non-ignored text file in the project, Markdown and scripts included. The trap is the project's own instructions. A build brief, a plan or a guard script that quotes the banned classes, common in projects built with an AI assistant, makes Tailwind generate exactly the classes they forbid.
The fix: in src/app/globals.css, @source not "../../docs"; @source not "../../scripts"; @source not "../../tests"; @source not "../../qa";.
Evidence: stylesheet search before (3 variables found) and after (0), 2026-10-28.