“Leaf” theme slider

Good afternoon.
Our site https://www.choim.org/ has problems.
The slider of the main page of the site does not work well, which affects the menu. This problem appears immediately upon opening the site and loading the slider. Previously, its size was 768×350 pixels, now it is smaller. Where exactly are the slider settings located?

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