So This website:
They have a background image on every page but when zooming, it doesn’t change – ever. Not to mention how fast it loads. How is that possible to have content zoom without the background image? I could understand if it was a repeated image but this is not.
On that site it looks as though it’s done by a script, as @rownage observes, but I’ve done it successfully in modern browsers using the (CSS3) “cover” property, i.e.
background-size: cover;According to my notes (hurrah for comments!) this A List Apart article is where I got my information from.On my (very much still-in-progress!) photo site, it looks like this at the moment. The background stays the same size when zooming in the browsers I’ve tried. Though it wouldn’t surprise me if Internet Explorer couldn’t cope with it.
As to how fast the images on that site load, the trick is simply a good choice of compressible image, well-compressed. The background that loaded when I visited their site is 1024×680 pixels, but because it’s mostly black and white with large areas of plain colour, it compresses down to a pretty tiny 74KB.