Some part of the forum doesn't show fully on mobile

[FireWolf29]

I know if anyone confused with the title cuz I'm not very good at English but here's go:
- On mobile, when the users go to the login or register page the entire page doesn't show fully. Furthermore, the users can't swipe the screen to see the hiding part.
(! please note that the users login on the embedded forum on my website not the real forum website)

[Israel <Nabble>]

ask them to change the position of their devices to landscape.