Sticky header issue (+ Image Carousel request)

Hi! When I scroll down the pages on https://inferriatevep.com/test/ the sticky header “shifts” a little on the left of the page… so I’ve a blank space on the right side of the header (see close to the magnifying lens). Why?

Second question. Example… https://inferriatevep.com/test/?page_id=280
In every product page I’ve putten a “image carousel”: is it possible to have alle the images full width raw but the same height? I need to have a landscape view on the PC but the correct view on mobile devices. Now is 940*300 pixels.

Thank you!