Imported CSS missing

[DavidPetrasek]

In ./src/index.ts I do:
import './style.css';

... but the build files .mjs and .js does not contain this import. Only thing which happens is style.css is copied into ./dist folder and is renamed to index.css. Then I have to manually add these missing imports to build files.

I want the build files to also contain this import, so the CSS is automatically consumed.

My tsup.config.ts:

import { defineConfig } from 'tsup'

export default defineConfig({
  entry: ['src/index.ts'],
  format: ["cjs", "esm"],
  dts: true,  
  splitting: false,
  sourcemap: true,
  clean: true,
})