Merge pull request #101 from wesbos/patch-1

clarify path to _app.js

Merge pull request #50 from emilbryggare/master

Add PurgeCSS explanation to README.md

Update README.md

Fix PostCSS config.

Remove next-css as not needed in Next 9.2

Update packages

Add purgecss to Next.js example

Update Next.js example

Merge pull request #39 from jimt/patch-1

Fix typo

Remove unnecessary instructions

Update readme

Update readme