Having issues theming

[theelicht]

I had some struggles with the component based theming, since I'm new to Vue.js and all that. I decided to straight up style using css in client/themes/<my-theme>/app.scss. It works perfectly fine when using yarn dev for local testing, but as soon as I build a docker container half of the css isn't loaded (admin area, etc.).

If anyone could explain the component based styling or explain to me why the css is overwritten, that would help me out a lot.