Samsung Galaxy A8 10" Tablet, Background Adjustment

Hi,

    My Wife has a Samsung Galaxy A8  10" tablet.

    The home screen background is light.  Reading the
white letter text for various icons could be improved
it there is a way to make the background darker
such as dark gray or blue.

     I went into Settings,  Display and Wallpaper, but
I could not find a method to set a darker background.

     If you know how, please respond.

        Thank You in advance,  John