I have a website that has a full-image fixed background that the content "floats" above. It works fine in desktop browsers, but the fixed background ends up scrolling on iPads and other tablets. This seems to be a common issue, but then I ran across this website, which seems to have a fixed background even on iPad's.

http://confitdemo.wordpress.com/

Any clue how they are pulling that off? I tried:

#content-wrapper.posts-page {
background-attachment: fixed !important;
background-clip: border-box;
background-color: transparent;
background-image: url("image path");
background-origin: padding-box;
background-position: right top;
background-repeat: no-repeat;
background-size: cover;
}

(This was copied from Firebug, which is why it's not shorthand).

But had no luck. Anyone get me pointed in the right direction?

Edit
Report