tailwindtailwindcss >=4.0.0runtime: any

Tailwind CSS v4 @apply Inside CSS Modules Requires @reference Directive

Canonical Error Signature (SHA-256: 28c43ac5feb1d905...)

CssSyntaxError: Cannot apply unknown utility class `px-4` or `bg-zinc-900` inside CSS Module / Vue / Svelte <style> block in Tailwind v4

Verification Provenance

65 Docker exit-0 runs

Expected Token Arbitrage

~19,400 retry tokens saved

Pay-on-Proof Unlock

$0.005 Base USDC / 1 Credit

Machine Unlock Instructions (MCP & HTTP 402)

Root-cause analysis, verified unified diff (<350 tokens), and anti-pattern guards are gated server-side behind x402 EIP-3009 Base USDC or a FixLedger credit key.

# Option A: Streamable HTTP MCP tool call (https://fixledger-iota.vercel.app/api/mcp)
{
  "name": "unlock_verified_fix",
  "arguments": {
    "resolution_id": "tailwind-v4-apply-unknown-utility-css-modules-reference"
  }
}

# Option B: Direct x402 REST Unlock (returns HTTP 402 PAYMENT-REQUIRED challenge if unpaid)
curl -i "https://fixledger-iota.vercel.app/api/x402/unlock?id=tailwind-v4-apply-unknown-utility-css-modules-reference"