Hibike Euphonium. Violet Evergarden
I can second both of these.
I didn’t recommend them earlier because I remember them most for their peak animation and story instead of beautiful scenery, but I won’t be surprised if they are extremely good-looking in terms of background art too.
MyTurtleSwimsUpsideDown@fedia.io 2 weeks ago
Violet Evergarden was the first thing that came to my mind, but I don’t have a strong enough recollection of the art detail to recommend it on my own. I’m glad someone with a better memory was able to give it its due.