Render HTML as an Image

I’m generating a coupon based on dynamic input and a cropped image, and I’m displaying the coupon using ntml and css right now, the problem is, printing this has become an issue because of how backgrounds disappear when printing and other problems, so I think the best solution would be to be able to generate an image based on the html, or set up some kind of template that takes in strings and an image, and generates an image using the image fed in as a background and puts the coupon information on top.