Principles
Mostly type. Boxes, shadows, and color only show up when they have a job to do.
There is one accent color, green. It marks the timeline, link hovers, and focus.
Borders are 1px lines that separate things. Home, resume, blog, and this page all use the same layout: a sticky label on the left, a column to read on the right.
Components never hard-code a color, size, or space. Change a token in static/css/tokens.css and the whole site follows.