Tailwind Cli tool is working for me in v4 or backward to v3 https://tailwindcss.com/docs/installation/tailwind-cli
what code on docker
RUN apt-get update && apt install nodejs npm -y
RUN npm install tailwindcss @tailwindcss/cli
npx @tailwindcss/cli -i ./src/site.css -o ./src/output.css --watch