Thanks for reaching out!
The background is not white, but has more of an eggshell color, hex-code is #efebe9
And here is a preview of what it looks like when I want to print it in grayscale: 
I hope this clears up what I mean.
Thanks for sharing – that definitely isn’t what I intended and I didn’t see it when I tested things out the other day, but I definitely see it in the screenshot! I’ll see what I can do, hopefully I’ll have something for you by the end of the week