Activate Secret theme

To enable it, follow these steps:

1. Press Win+R to open a run dialog, type “regedit”, and press enter.
2. Browse to: HKEY_LOCAL_MACHINE > SOFTWARE > Microsoft > Windows > CurrentVersion > Themes > Personalize
3. If there’s no Personalize folder, right-click Themes and select New > Key. Name it Personalize.
4. Right-click Personalize and select New > DWORD (32-bit) Value. Name it AppsUseLightTheme and set its value to 0.
5. Perform steps 3 and 4 again in the following location: HKEY_CURRENT_USER > SOFTWARE > Microsoft > Windows > CurrentVersion > Themes > Personalize
6. Log out of your account and back in.