Changing font size in all the posts

Hello.
After the latest WP update, I found that the font text in all the posts is huge.
It is not possible to reduce it with “Typography” to “Customize” or with the additional CSS as far as I know.
I should change it post by post and it’s really annoying.
I wouldn’t want to remove the block editor and go back to the classic one, but is there a way to reduce the post font size all at once, with just one general code for all (published and new) without working them one by one?
Thank you.

• This topic was modified 2 years, 9 months ago by Jan Dembowski. Reason: Moved to Fixing WordPress, this is not an Developing with WordPress topic
• This topic was modified 2 years, 9 months ago by James Huff.

The page I need help with: [log in to see the link]