Excellent point.
In general, printing backgrounds is a browser feature, and users should mark this option manually in the print dialog:
Clik here to view.

But… There’s a really cool hack -
.box-with-background {
-webkit-print-color-adjust: exact; // For Chrome & Safari
color-adjust: exact; // For Firefox
}
This implements two little-known css properties -
Notice this does not work in IE or Edge.
Image may be NSFW.Clik here to view.
