Text in submit button is not aligned correctly on mobile

Here’s the link to my codepen: https://codepen.io/zukululushikufu/full/abvOYvx

I’m almost finished with my survey page project and everything looks fine on desktop but when I tried to have a look at my survey on my phone, the text in my submit button looks left aligned.

I’ve tried changing the text-align and the margins but that didn’t seem to help. I don’t know what’s wrong can anyone help me out?

EDIT: Just found another problem, whenever I tap on a field and bring up my on screen keyboard my background image changes size. Is this normal or does this need to be fixed?