An interesting look at using padding only on the very lowest element within a hierarchy (as Samantha says, the atoms of your design) and therefore setting it globally. It's a logical approach, though I'm glad to see I'm not the only one who took one look and thought "surely margins would be a better approach". Still, a useful tool and clever way of thinking about object spacing that could make your CSS a lot more efficient.
Note: this was originally part of a full article titled "Thoughts from around the web" and the 13th post in my New 52 challenge. That article also linked to a blog post on logo design and a critique of modern "culture-fit" hiring practices.