How to deal with the relationship between desktop, background and interlining in sketch

Both the mesa and the mezzanine are backgrounds, and the background is a foil to still life, which is a subordinate relationship. Because we mainly show still life, the background should be weaker than the theme-the color of the background should be gray and relatively weak, so as not to grab the attention of the theme.

There are elevation and plane in the background, and their brightness is different-with distance, elevation and plane can be distinguished.

(The theme should be detailed, with strong contrast between black and white. You have to show the nearest thing the strongest-we will think it is at the front, and the farthest thing is the weakest, so we will naturally retreat. )