Custom code suddenly stops working

I implemented a custom grid code to function as a custom front page for a website. It was working fine, until one moment, instead of showing a full grid, it was only showing the first three (I have set it so that there are three images per row). Later it was showing things in all sorts of weird orders and now it is showing only two when I have put in four photographs… upon inspecting the element, the code seems to have some stuff I don’t remember having seen before. Is this a hack? What to do?

Custom page: http://www.joonaniskanen.com/426-2

Original code for grid: http://tympanus.net/codrops/2013/04/17/responsive-full-width-grid/

I am lost! Please help!

Thank you!