How to build bundle.css using parcelify and stylus?

Question

css

The task is the following, there are plug-ins via npm (for example, jQuery plugins) with their own styles, and there are custom styles that I write on stylus. I want to collect all this through npm-scripts into one bundle.css and include only this one file with styles. Separately, plugin styles are collected in one bundle, I tried to import this bundle into main.styl, but they are not connected.
Script example:

"scripts": {
  "parcelify": "parcelify src/js/main.js -w -c src/styl/lib.css",
  "stylus": "stylus --out build/bundle.css src/styl/main.styl",
  "build-css": "npm run parcelify & npm run stylus"
}

In the main.styl itself , I wrote.
@import "lib.css"
In short, the task is to add lib.css to bundle.css, i.e. combine two into one.