about Tailwindcss -i -o problems

I installed node, npx, and tailwindcss according to the instructions. However, when I typed npx tailwindcss -i ./input -o ./output --watch .., output.css was generated, but there was nothing in it. When I executed run server, I couldn’t apply the effects of tailwindcss.

Can anyone help me? thanks…

Welcome @yangmo0113-alt !

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