Refactor the whole configuration

Reviewed-on: #1

assets/README.md

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+# assets
+
+The wallpaper used here is watermarked, the purchased version is stored in the secrets, inaccessible to the public.
+If you too want the watermark-free version you can [purchase it from the artist](https://wboss.huotan.com/p/TEcHBI)
+for mere ¥12. The artwork looks great, I'd highly recommend it.