how to create a masonry grid of 16 boxes?

lilianedias
Community Novice

Hello! I would like to create a masonry grid of 16 boxes, where each box corresponds to a theme, as in the image below.

grid

I saw this in this link:

https://ucdenver.instructure.com/courses/336339/pages/sehd-course-progress-template-commencement?mod...

but I do not know how. I tried using bootstrap, but to no avail. Can anybody help me? Thanks.