Adjust Background-Color of Employee-Widget

I am using round profile pictures for my employees. Now I want to adjust the background color of the widget! The line where the widget is placed in has already the correct background color but the picture containers of each employee is still white even when I adjust the background color of that widget in its setting on the sidebar! Any ideas?

Thanks for your help!!!

Hello there,

Is there any URL you could share here so I can have a closer look?