The new gallery weblink style is dark, you can also edit the CSS in wl/css folder to customize as you wish, I just did it for my server.
I second this, I have added photoswipe on many websites, it works great on mobile and desktop.
I had this same problem, one line fix in /wl/css/gallery.css or folder.css add this line at the end
hides "download all" button on the main link page when there is not a 'path' in the URL!
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