How to reduce the intensity of bright colours in iOS 14 for iPhone/iPad/iPod Touch

Open the Settings app . Note: The Settings app icon may appear in a different place on your home screen than shown in our example, below.
In the Settings app, scroll down and select Accessibility from the list.
On the Accessibility screen, select Display & Text Size.
On the Display & Text Size screen, select Reduce White Point to set the toggle switch to On.
The intensity of bright colours is automatically reduced to 75%. Use the slider to adjust the intensity further.
When you are happy with your settings, you can return to the home screen page of apps by:
- On devices with Face ID: Swipe up from the bottom of the screen.
- On all other devices: Press the home button once.