How could I obfuscate ReactJS app during the npm run build phase?

I have found the javascript-obfuscator package on npm, but when I do the obfuscation with it using javascript-obfuscator ./build --output ./build/obfuscated; rm -rf build/static/; mv -f build/obfuscated/* build/, app stops looking like it should (css goes crazy: layout displays as though some csss are missing) without a hint of what might have gone wrong.

Any help is appreciated.