What can cause all content to slide out when opening a modal window?

Question

css

I'm using a modal window from the alpha version of bootstrap-4. Everything moves out in the background as shown in the picture.

and this happens in chrome and ff, but in the latter and edge everything is fine. Plus in chrome it works fine when i browse through device mode.

Link to the page - on the third screen, when you click on the first tile "Do you have a toothache?"

Answer 1

because when the modal is open, the padding-right style is assigned to the body tag. This is either a modal.js bug from bootstrap, or you added something yourself

Answer 2

And wrap everything in the body tag in .wrapper. Helps avoid many problems in the future