css.md

CSS

• ESLint
• Oxlint

ESLint

To use ESLint with CSS files containing Tailwind CSS @apply directives, first install the @eslint/css plugin and the tailwind-csstree custom syntax.

npm i -D @eslint/css tailwind-csstree

To lint Tailwind CSS classes in CSS files, ensure that:

• The @eslint/css plugin is installed and configured.
• The tailwind-csstree custom syntax is installed and configured.
• The plugin is added to your configuration.
• The settings object contains the correct Tailwind CSS configuration paths.

Flat config

Read more about the ESLint flat config format

// eslint.config.js

import css from "@eslint/css";
import eslintPluginBetterTailwindcss from "eslint-plugin-better-tailwindcss";
import { defineConfig } from "eslint/config";
import { tailwind4 } from "tailwind-csstree";

export default defineConfig({
  // enable all recommended rules
  extends: [
    eslintPluginBetterTailwindcss.configs.recommended
  ],

  // if needed, override rules to configure them individually
  // rules: {
  //   "better-tailwindcss/enforce-consistent-line-wrapping": ["warn", { printWidth: 100 }]
  // },

  settings: {
    "better-tailwindcss": {
      // tailwindcss 4: the path to the entry file of the css based tailwind config (eg: `src/global.css`)
      entryPoint: "src/global.css",
      // tailwindcss 3: the path to the tailwind config file (eg: `tailwind.config.js`)
      tailwindConfig: "tailwind.config.js"
    }
  },

  files: ["**/*.css"],

  language: "css/css",

  languageOptions: {
    customSyntax: tailwind4,
    tolerant: true
  },

  plugins: {
    css
  }
});

Note: Legacy config is not supported for CSS files as the @eslint/css plugin requires the ESLint flat config format.

Oxlint

Oxlint currently does not support CSS parser integration for this use case. Because Oxlint currently only supports JavaScript-like files, eslint-plugin-better-tailwindcss cannot currently lint CSS @apply directives through Oxlint.

You can continue using ESLint for CSS files until broader parser support is available in Oxlint.