If you're taking notes in a dimly lit environment or prefer dark themes in general, you can display RemNote's interface in dark mode by selecting the appropriate option in Settings > Interface:
The System option will follow your operating system’s settings, if it has them (this can be helpful, for instance, if you have your computer configured to switch to dark mode after sunset).
Unlike most settings, the current value of the dark mode setting is maintained individually for each device you use RemNote on, so you can, for example, use dark mode on your laptop and light mode on your phone, without having to toggle it back and forth all the time.
You can also toggle dark mode on the fly using the Toggle Dark Mode omnibar action:
Dark mode in the RemNote Reader
By default, the RemNote Reader will use the same dark mode setting when displaying PDFs and other documents as the rest of RemNote's interface. Occasionally this will make the document hard to read, and you might prefer to use a different color scheme for documents anyway. You can override the color scheme for documents with the Change theme option on the Reader menu: