@amandam I did try coding it. The problem is the lightbox constraints. You can call for content any way you like and trigger the box by any means, but the lightbox won’t conform to the width of the content called.
Here is what I believe may be happening:
Lightboxes may independently check formfactor. On non-mobile sites, this check should be disabled. The lightbox performs the check and sizes itself accordingly. And so, you get a background that’s “normal” but a lightbox area that has conformed for mobile use.
Customer care is check out the issue now. They are running into the same issue, apparently. So, I’m waiting on their fix.
Fingers crossed.