Create gallery for an existing site + backend for images

Create gallery for an existing site + backend for images. The CMS is already working. I already posted the project for a freelancer that didn't complete it and his freelancer account is suspended. I have part of the code that he has written: see here [login to view URL] My site is: www dot image-school dot co/gallery (replace dot with .) You need the take that code that he wrote there, and make sure that it works on my site. I also have a working CMS in php - you need to integrate and manage the images there. Very nice and friendly system You can see attached the code that he wrote (I saved it from the link), as well as how the gallery needs to be like. I will be keen about the colors and margins. It's a work of a few hours. Your bid should be final that everything is working. Please note that from a bad experience (this freelance already charged me $25 which didn't worth it) I don't pay any milestone before the project is finished.