Hello, I am pretty sure these are bugs, but happy to hear otherwise.
I am trying to edit the Dark theme so that I have Dark UI and white pages + black text.
Switch the page color in Main Editor to #fff, and text to #000 and fixed width background to #fff. You cannot set the Page View background to white. If you do the text resets to black page / white text. I am pretty sure I can achieve this on Mac (have page view with a #000 background, #fff editors (page) and #000 text .
The background of index cards titles is always black (or, rather, it’s the color that was in the dark theme that is edited, so blue-ish for Solarized Dark etc.) Even if I change the background color of index cards themselves, if I try to edit their titles, the background of the edited title becomes black , while the color of the edited title’s font remains black as well (so same color as the index card, which is I guess a correct behavior).
The dark color editing the Index Card Title is the background color for all text input fields. The only way to make you see when you edit, is to make that color lighter, which has an effect on the overall Theme. Making the Index Cards completely white and the text black is not a problem.
The fixed width Editor works well with a white background and a white page background, although this looks the same as a full width Editor, but with wider margins.
Setting the background to black works as a charm as well.
Many options come along with a Theme, so you might want to save your personal options to file: File > Options > Manage > Save Options to File… to be sure you can return to the state before loading the Theme.
Here’s your personalized Theme. Unzip it to a .scrtheme file and Window > Themes > Load from file… to see it after restarting Scrivener. Dark Paperwhite.zip (16.0 KB)
If you like it, you can Windows > Themes > Import Themes… and point to the Dark Paperwhite.scrtheme file.