Copy a css file from assets/styles to dist/styles using manifest.json

I am trying to copy a single file from assets/styles/mystyle.css to dist/styles/mystyle.css, but I don’t want modify gulpfile.js. I want to do this from manifest.json (using globs.css, maybe?)

Is there any way to do this?

Depends what you want to do, but I usually just include the CSS file I need in the main.scss chain:

@import 'mystyle.css';

All the CSS rules are then part of my main.css production file.