Cannot close popup images

I love this theme and have almost everything figured out. On some pages I have (thumbnail) images set to “link to media” so the viewer can see a larger view. However, when the image pops up, there is no way to close it. I don’t see a close button and simply clicking on the larger image doesn’t close it either. I have to use my browsers back button to close the popup.

I added a quick demo page here so you can se what I mean…

https://www.midislandcastaways.com/demo/

Any thoughts?