The Dark mode of Petal Search is based on the Dark mode of EMUI (which is only supported in EMUI system 10 and later versions. You can check the version information by going to Settings > About phone). To enable or disable the mode, go to Settings > Display & brightness > Dark mode，and then you can use the Petal Search with Dark mode.

If your phone is running an earlier EMUI version, update it to the latest version by going to Settings > System & updates > Software update.