[refactor] Lift the theme contract out of the Tailwind config - #5740

100 tests  ±0   100 ✅ ±0   14s ⏱️ +4s
  1 suites ±0     0 💤 ±0 
  1 files   ±0     0 ❌ ±0 

Results for commit d9a1dc1. ± Comparison against earlier commit b7a5916.