I moved your comment over to a new thread as this is a separate feature request. Based on your post, it sounds like you're requesting a specific app setting for Pandora to switch over to dark mode, rather than switching to dark mode for your Android phone completely.
Pandora now supports Dark Mode on Android devices updated to Android 10 and running the latest version of Pandora.
To manage your Dark Mode settings:
Go to your Android Settings.
Next tap Display.
Toggle Dark Themeto turn Dark Mode on and off.
Your selection will be reflected in the Pandora app.
Hope to see you around the community space more often! 🎶