Getting unexplained side scroll on small screen size

There’s some side scroll on this page that I’m building when I get down to 320px screen size, and I’m 99% sure it’s because of something in the section_testimonial32 (see screenshot).

I just can’t for the live of me figure out WHAT is causing the excess width. Any ideas?

P.S.: Yes I do realise 320px is a fun-sized screen, but at this point it’s as much about the brain-tease as anything. Besides, it’s marked in the Designer, so I figured I should make it work.

Here is my site Read-Only: Webflow - Icelandic Made Easier

Live version: Speaking course draft