Turn on Dark Mode for a great viewing experience in low-light environments.
Go to Settings, then tap Display & Brightness.
Select Dark to turn on Dark Mode.

Touch and hold the brightness bar.
Select to turn it on or off.
If you can’t see Dark Mode in Control Centre, you can add it.
Touch and hold a blank space in the Control Centre to edit the screen.
Tap Add a Control at the bottom of the screen and select to add it to the Control Centre.
Go to Settings, then tap Display & Brightness.
Select Automatic.
Tap Options to set a schedule for Dark Mode.
Find out how to use Dark Mode on your Mac.