I've looked at Shadowbox to see if there's a way to accomplish this via javascript, and I'm just not sure that there is while also putting images on pages as image cards.
Currently, I embed images into pages by making them inclusions and making the image a card. Great. But I have to make the images small so they don't overtake the entire page and get in the way of the text. Some of the images are really nice though, and I'm sure people would like to be able to click on them to see them better. As is, there's no good way to do this.
The expected behavior would be to see a small image, click on it, and a larger version comes up in an overlay lightbox that darkens the rest of the page until you close it. Wagn will know that the image is an image card, so maybe it could be part of the inclusion options alongside size and setting margins we could set showing in a lightbox as a possible option and then somewhere in the CSS define the amount of the screen that the lightbox can maximally take up relative to the full size of the image.
There may not be a way to adapt some existing widget to easily do what you want, but if the information is on the page, you can manipulate it with javascript to do virtually anything. If the image is displayed on the page, then you can get the URI and construct the elements necessary; it is a small matter of programming what you want it to do.
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