Many users are wishing for a dark layout, in particular if the surrounding lighting is bad. The dark mode on your Huawei device is a battery saver and it is also said that the dark mode is better for the eyes.

Note: The dark mode can also be activated over the quick settings.

Android 10 | EMUI 10.0
Dark mode -  Open the  settings
Dark mode -  Tap on  Display & brightness
Dark mode -  Activate or deactivate  Dark mode
  1. Open the settings
  2. Tap on Display & brightness
  3. Activate or deactivate Dark mode

Huawei Instructions