Homepage: Image shows differently on desktop and on mobile

Hi Community,
The site is at hhtps://francoismontrelay.net
I have a problem with my home page: Header media is an image. On a mobile or on a tablet, it shows very well. On a desktop, I can see the top menu and the image like a banner, completely different.
I want the full image, of course.
Can someone help?

Thanks in advance



Please try to increase the header container height:

.header-image {
    height: 650px;