How do I change state on button when lightbox viewed

Hi Nancy, see attached the 'mad scientist' approach; when the three layers in the lightboxed slide have been clicked a variable is set to true. On the base slide, there is a transparent shape that sits just 'underneath' the lightbox's X button. This shape has a hover trigger that changes the text's state to Done, but only if the variable is true. So, when I close he lightbox, the mouse then sits on top of the transparent shape and if the variable is true, then the text's state changes. I hope someone comes up with an easier solution

Edit: I didn't know that HTML5 was a requirement, don't bother with my idea then, it won't work.