Before we started building the shelves, I rough sketched a drawing of how I wanted them to look. Since my sketches make no sense to anyone but me, I’ve “translated” it into something you can (hopefully) understand:
This is what I envisioned the shelves looking like if you were a giant that was looking straight down on them. I wanted to build a hidden inner frame that the top and bottom boards could sit on/screw into.
To make everything look as seamless as possible, I wanted the width of the top board (AKA top of the shelf), hidden side support brace boards, and bottom board (AKA the bottom of the shelf) to equal the height of the front piece (AKA the front of the shelf) so that when everything was put together, each shelf would look like one chunky piece of solid wood.