Windows 10: Task Bar Color

Somehow, the task bar changed to plain "light", and the box in "Start, task bar, and action center" under accent colors in Settings is not activated. Can someone explain how I can re-activate this box so I can revert to the color I chose for the task bar?

:)

 

Accent color for start, task bar, action center

 

Task Bar color

Can not change task bar color. The Start, taskbar, action center in Personalization, Colors is not active.

 

Same color for task bar and tile bar?

When I change the color in Windows 10 from the settings, I do get the correct color in the title bar but I get some kind of blue on the task bar because the task bar has some dark blue background and it mixes the colors. How do I get rid of the dark blue
background in the task bar so that I can get same color on both? Disabling transparency is not an option as it disables by background image in the start page.