What exactly is it you are trying to achieve here?
The background property is shorthand property used to apply various background effects to an element, such as a <div>
I’m not sure it really makes sense to apply a background image to an image.
Well, I’m glad you managed to find a solution to your original problem, but I still can’t see any practical value to replacing one image with another in this way.
Also, what’s going on with the height:0px?
I wouldn’t know how to add an element to a page using CSS.
You can do this easily enough with JavaScript (or just in the HTML), but that doesn’t deem to be what you’re asking.