Why does the image jerk when scrolling?

Question

css

travel-spy.ru
When scrolling down and then up again, the slider bar (the topmost large one) twitches. I can't figure out why, which property affects it.

Answer 1

Because of this: https://c2n.me/3RwX3LJ
You have a sticky menu at the top, when the scroll moves a little down, the background immediately jumps by 65 pixels.
You can fix it like this: https://c2n.me/3RwX9BD , https://c2n.me/3RwXaKc
I did not check adaptations for small screens. This will have to be checked by yourself.