Then, remove the npm stuff again (`rm -rf assets/{node_modules,package.json,package-lock.json}`) and follow the [Phoenix/Tailwind upgrade instructions](github.com/phoenixframe...)

Then, run the Tailwind upgrade tool. This needs to happen in the project's root directory:

`cd ... && npx @tailwindcss/upgrade --config assets/tailwind.config.js --force`

First, install the npm version of Tailwind v3, including the plugins referenced in your Tailwind config. This needs to happen in your assets directory.

`cd assets && npm install tailwindcss@v3.4.17 @tailwindcss/cli @tailwindcss/forms @tailwindcss/typography`