Standard ease
cubic-bezier(0.2, 0, 0, 1)
One curve for the entire system. No bounces, no springs.
Durations
140 · 240 · 420 ms
Fades and tonal shifts only.
Entrance
Fade + 4px translate-up
Staggered. Never scale. Never off-screen.
Press
1px translateY, no scale
Fill darkens one step on press.
Focus
2px ring · 3px offset
Secondary brown at 40% opacity. Never a solid border.
Tonal shift
Background tier, not shadow
Depth is a paper tier. Elevation is never a box-shadow first.