Angular 2: External Stylesheet Import

Question

I am simply trying to import a stylesheet to my component and I keep getting an error that it cannot be found:

@Component({
    selector: 'repositioning',
    templateUrl: './repositoning.html',
    styleUrls: ["app/vertical-timeline.css"]
})

...and the file is there:

MacBook-Pro:app user$ ls
app.component.ts    app.module.ts       main.ts
app.html        app.scss        vertical-timeline.css

am I missing something simple?