amateurish browsers button buy clicked computer control fixed font free friend installed page paypal problem scroll side signed trial website

I just signed up for a free trial, and installed the buy now button on my website. I clicked on the new button, and the page I was taken to looked very amateurish - the font was way too big, and you had to scroll from side to side to see it all.

I tried again on a friend's computer, and it looked OK. Is this a problem with certain browsers? Is there any way it can be fixed?

It's the PayPal page you are talking about. We don't control that page, PayPal does.