Issue with scroll and borders

Hello there!
I’m having an issue between borders of my page and the scroll possibility of this page. To be more precise, the page contains a text (which need to be scrollable), and a thin black border of the screen (23px of margin). As I don’t want to see the text between the border of the screen and the black border of my page, I add a white border in this space on top of all.

But I have the impression that all of these border make my page non-scrollable when the site is published while in preview mode it works perfectly! I don’t understand why and don’t know what can I do to keep my black border and my scrollable text. I’m researching a “free” way to solve it because i’m on the free site plan.

Sorry if it’s not really understandable, i’m come from France and my English is not perfect :sweat_smile:

Thank you in advance for your help!


Here is my site Read-Only: LINK
(how to share your site Read-Only link)