Why a transparent blue background?

Question

Anyone please explain why a transparent light blue background appears when I click on the page only on mobile screens?
Iam stuck....
https://code.sololearn.com/WJnp8ydeo8AZ/?ref=app

Answer 1

You mean default blue color of sololearn app?

Answer 2

I think it the display of your phone ➡📳

Answer 3

Or sololearn is crashing