I don't know how to fix that...

Hi there!

On mobile and Ipad, when ever someone tries to write a comment I am getting a nasty gap on the right side of the page.
It looks like the entire page get's a margin, or a padding.

I tried tones of things to fix that issue.
But I simply can't figure out how I can possible avoid it.

Does anybody know how I could fix that nasty gap?

Here is the link the the page it's happening:
https://gousa.site/nein-sager/

When you go to the bottom, you have the comments section.
When you are on mobile, and you try to write a comment... peng.
The entire page "moves" to the left.

Thank you so much for any little help!
Appreciate it!