React-WebPack Project Can’t Be Rendered?

  node.js, question

React-webpack generator based on yeoman;

Some project catalogues are as follows:


In general, command line input

npm run start

It can be enabled normally, but the main code: GalleryByReact.js cannot render the content. I finished the export as follows:

export default AppComponent;

The result is still wrong

No code, no error message, the gods can’t help you.