The screen that you write and check directly in WordPress is different from the

1.https://ifh.cc/v-7lNbld
i have a problem
If you write on the web and set it on mobile and look at the screen, there is a blank space on the side.
The problem is that, unlike what you see on the web, when you access the site from a smartphone, the text fills the screen with no space.

2.https://ifh.cc/v-aF5vjT
I need help The screen is different from the web screen I wrote on my PC and the screen I saw on my smartphone, so it's a problem now

The screen that you write and check directly in WordPress is different from the screen you see directly on the mobile screen