Modern floating shelves - "check-box" design

I am so excited to show you my favorite project. Since I saw these types of shelves on Pinterest, I wanted them in my house. The difference was that they were made out of plywood, and the black frame was, I believe black tape. I asked my husband to build them for me, of course. He changed the project, so, instead of using black tape, he built some thin square frame, and instead of using plywood he made the "check" sign out of oak wood.
The entire process consists of:
-making the thin square frames
-building the templates for the "check" sign
-building the "check" sign
-sanding them to be as smooth as possible
-routing the slots (for the frames and for installing them on the wall) on the back of the shelves
The entire process is very well explained on our blog, and also in a short video