HTML background image offset by x pixels from the center

Question

I\'d like to put an image as the background of a webpage but have it offset by some number of pixels with respect to the center.

How can I do this?

I want:

Answer 1

There's no obvious CSS answer. You would either need to use JavaScript to calculate values or do something tricky. You can try keeping the background-position:25% center and adding position:relative;left:-50px or margin-left:-50px but those might not work depending on how you are using the DOM element.