Responsive behaviour

Breakpoint	Columns	Margin	Gutter
Desktop, 1080 px and up	12	fluid, 80 px at 1440	24
Tablet, 640 to 1079 px	8	32 to 48	20
Mobile, below 640 px	4	20	16

Below 640 px:

• A short dialog becomes a bottom sheet; a long or multi-field form goes full screen.
• Targets are at least 44 px.
• The shell’s sidebar becomes a drawer.
• Every screen is checked at 375 px.

The base unit is 4 px and spacing comes only from the scale.