Making Bg Resize To Browser Window...but Not Shrink

[jc624]

I’d like the background image to resize proportionally as you can see the link below (this I know how to do), but then stop resizing if the user squishes the window to be much longer than it is wide(this is what I'm try to accomplish).Here's an example:http://www.jdda.com/#/homeDoes anyone have any ideas how this is done?Update:I found another example:http://www.salomon.com/uk/