Components
Progress & loading
A spinner is for an action under a second with no known shape. Everything with a shape gets a skeleton that mirrors the real layout, so nothing jumps when the content lands.
Spinner & skeleton
Progress
Avatar, kbd & code
Avatar
Groups overlap 8px with a 2px surface ring and cap at three plus a count — three faces and "+2" says "a few people" in a fifth of the space eleven avatars would take. The accessible name is the full list; the visual is the summary, the label is the truth.
Kbd & code
⌘ K search anywhereEsc close panel
L14 RP80432lot_plan The keycap has a 2px bottom edge — the one pixel of dimension in the system, because a key is the single thing here with a physical referent. GdCode has no background by default: a tinted box behind every identifier in a sentence turns prose into a chequerboard, and the typeface is already the signal.