Is there any way to automatically remove unused CSS (and JS) code?

Question

css

For example, there is a CSS file, there are many classes. And the HTML markup uses only one class from the entire file. Is there any plugin for faucets and task runners that removes unused code? webpack, Gulp is desirable. Isn't that what CSScomb is for?
Same question for JS. There are the same jQuery/plugins for it. Only a pitiful part of the entire code for a small feature on the site is used - is it somehow possible to extract only the "necessary" code?

Answer 1

Wang that bootstrap is used))
Then customize collect getbootstrap.com/customize

Answer 2

https://www.npmjs.com/package/gulp-uncss