A 40px pill that starts an action, with five variants ordered by emphasis: filled, tonal, outlined, text, danger.
Rules
- btn-filled: the screen's single primary action. btn-tonal: important but secondary. btn-outlined: a neutral alternative next to a filled. btn-text: dialog actions and in-card links. btn-danger: a confirmed destructive action.
- Sizes: 40px by default, btn-lg 48px for mobile and forms, btn-xl 56px for a hero.
- On press the radius goes from 20 to 12px (Expressive morphing). Label 14px / 600, sentence case, never truncated.
- Never a fixed width. If two buttons no longer fit, they stack full width with the primary action on top on mobile.