The theme has a responsive widescreen header. This mean depending on the screen size, the image will adjust to fit so there will be no gaps. Because of the responsiveness of the header, you will see the image shift the position depending on the screen size you are viewing the theme with. If you go to our demo site, you will also see the responsive header working. Weebly’s image perfect editor crops the image you upload. So if you want to limit the movement of the header image, you can use a larger monitor (24″+) to upload the header image. This way you can upload a longer image so the image will always stretch max height. This will help minimize the adjustment of the image in different screen size.