[General] Problem after installing fonts

[SasoN]

Hey! I tried to install fonts according to this tutorial: https://mods.mybb.com/view-resource/custom-font
after I saved the changes in "global css" my forum became wide, both in the default theme and MyTrade theme. Why this is happening? Thanks!
My forum:  http://smartsense.000webhostapp.com/index.php

[.m.]

there is a mistake in the chosen location of the global.css
- remove the code you have added in both the themes.
such code needs to be added in advanced mode of the stylesheet editor

[SasoN]

there is a mistake in the chosen location of the global.css
- remove the code you have added in both the themes.
such code needs to be added in advanced mode of the stylesheet editor

Thanks. I removed the changes but the forum is still wide, in both themes. is there a way to remove the changes completely?