Tailwind Build Failures : Why Your Classes Don't Render

The Tailwind compiler emits ONLY the utility classes it can DETECT in your source files. Every "Tailwind is broken" report is one of :

1. The compiler did not see the file containing the class.
2. The compiler saw the file but could not parse the class as a complete unbroken string.
3. The class was detected, compiled, but a stale build cache served yesterday's CSS to the browser.
4. A version-specific regression in v4 or Turbopack swallowed certain class patterns silently.

This skill is the diagnostic flow for all four. Always go top to bottom : root-cause-first.

Companion skills :