To break the monotony, Microsoft introduced dark theme with its Windows 10 Anniversary Update that rolled out in early August 2016. The black theme is known as the Dark Mode in Windows 10 Anniversary Update; you might want to know the dark theme was available even in the earlier build, buy you had to edit the registry to activate it.
However, the dark theme is not available on all Windows apps; only a few and mostly native Windows apps can show the dark theme. A buzz kill for people who were looking forward to the dark theme.
How to enable Dark Theme on Win 10 Anniversary Update
First thing first, how do you enable the default dark theme on Windows 10 Anniversary Update? Well, it is as simple as pushing a toggle button on. Go to Setting > Personalization > Colors. You will need to scroll down and click on the Dark checkbox under the ‘Choose your app mode.’
Immediately, the Settings app will turn dark, as well will many other native Windows apps. You will notice other apps will remain as they usually are; because it is up …read more
Read more here:: How to enable Dark Theme on virtually all Apps in Windows 10