More carpentry "skills"

I have had the idea for a long time to build bookshelves downstairs on a short wall by the furnace which can't be used for anything else. Because of the furnace room door, it is only wide enough for paperbacks. Below is the result of my (somewhat) careful planning and (not very) careful craftsmanship. Most of the planning was how to build it so that my less than quality craftsmanship would not show too badly. Anyway, it's sturdy and anchored to the wall in case of earthquake. As usual, I enjoy my own handiwork more than the quality merits. It is made of low quality lumber, materials cost about $60. Then there were the tools I "needed"...