I'm having a problem when import a Class outside its folder in Js. Here's my directory tree:

When I try to import Class1 from Client, there's an error occurs:

Client/index.js:

export { default as Class1 } from "./Class1";

Client/Class1.js:

class Class1 {
    static hello() {
        console.log("Hello");
    }
}

export default Class1;

Please help, many thanks!