Night mode is not working on android

Description of the issue:
I enabled night mode in all the possible ways.

  1. I enabled it from settings
  2. I enabled it from chrome://flags
  3. I enabled it from brave://flags
    But I’m still not able to get dark mode on all the sites

How can this issue be reproduced?

  1. Enable night mode
  2. It just doesn’t work

Expected result:
All websites should have night mode

Brave Version( check About Brave):
1.24.86

Mobile Device details
Motorola G 5S +

Additional Information:
Android 8.0.1