[Solved]-CSS - You may need an appropriate loader to handle this file type-Reactjs

you only have a scss loader setup so once its hitting a css file it doesn't know how to parse.

{ test: /\.css$/, loader: "style-loader!css-loader" }

should get you up and going.

edit:

also if you are using scss why not just change app.css to app.scss that way your css type is consistent and don't have to include the css loader. i would say that is the best solution.