Ok, I found the issue because I could see the login page was not styled correctly either. The following file has been corrupted by some process:
http://david.uchylas.net/panel/filemana ... s?v=3.30.1
I compared it with the original file (on our server):
https://demo.photo.gallery/panel/filema ... s?v=3.30.1
Your file has some corrupted chunks in it, cluttering and corrupting the CSS. From the following line, there is some unicode junk and missing almost 1000 lines (when un-minified):
Original:
Try to re-upload the file? You can download it from the demo.photo.gallery link. Not sure what happened, but some process on your server has corrupted the file.