This isn’t exactly about making background images in CSS for a site, so don’t mark it as a duplicate just yet.
I need to replicate the following background, but in CSS. I have a variety of gradients implemented on the site but this is more like a darkening around the edges of the screen, and I don’t know how to implement this, particularly in CSS. If there’s a good way to do this with images please let me know.

Thanks!
You can try inset
box-shadowhttp://jsfiddle.net/46JxH/Or background image with
background-size:100% 100%;.