One easing curve and three durations, with Tailwind's transition defaults pointed at them.

Every transition in the project ran on `ease` or `ease-out` — the browser default, and the least characterful curve available. `ease` eases both ways: it spends its opening accelerating before it settles, which blunts the start of a change that ought to feel like a reply. The new curve leaves immediately and settles slowly.

Durations are named for their job rather than numbered. The agent's change marks keep their 600ms as `linger`, which is the one duration here that is not feedback — a fade nobody is waiting on.

Setting `--default-transition-duration` and `--default-transition-timing-function` to the same tokens means the fifteen `transition-*` utilities already written pick the curve up without being edited, and a utility and a hand-written rule beside it now resolve to the same 120ms and the same cubic-bezier.

`--ease-*: initial` first, so `ease-in` stops resolving to Tailwind's curve. One curve is the point; a second one nobody chose is not.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

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### Stack

Merge bottom-up. Each PR targets the one below it, so every diff reads in isolation; GitHub retargets the child automatically as each parent merges.

1. #9  — Emit all theme tokens, fix callout colours, load Inter  ←  `main` 2. #10 — Add two-stop shadow scale tokens 3. #11 — Add radius tokens and replace bare rounded classes 4. #12 — Add type scale tokens, replace arbitrary font sizes 5. #13 — Add easing and duration tokens, set transition defaults 6. #15 — Add one focus-visible outline rule for all controls 7. #16 — Scale buttons down on press 8. #17 — Add tabular-nums to figures and balance plan headings 9. #18 — Shorten empty states and composer status copy 10. #19 — Add entrance animation for newly arrived items

Plan: `docs/superpowers/plans/2026-08-04-design-token-foundation.md`