White color Tab background and logo background

I have some doubt about the color of the Tab backgorund. When I put that color in white, as well as the Player background in white, I notice that the color of the tab background of the player is not as white as the Player background, but is like a light grey. Why does happen this color change if I want it to be white as the other part of the player?

Also, there's no way we can change the color part where the logo is placed in the Storyline modern player? Because even when we upload a picture in .png without background, the logo always has that grey background we are not able to modify.

Hope anyone can help.