On the UK website, the images and website respond to the size of the browser. You can enlarge it as much as you want and the image stretches filling the browser so you do not quite see the bottom of the website.
Just tried this after reading your post, how sneaky of them. Everything remains the same size except the main iPad mini image - it literally gets larger as the window enlarges!
Anyone with smaller screens, you should be able to see how the iPad in the top image is smaller than the one in the second; everything else remains the same size.