Hey @seank you left an empty href for your share link, can you please edit the post and add in the link?
As far as customizing the color of the lightbox background you should be able to do the following
<style>
.w-lightbox-backdrop { background: rgba(0,0,0,0.9) !important; }
</style>
Just edit the rgba color and that should do it, you may need an !important tag, might not.
Let me know if you have any trouble.
Thanks,
Waldo