Grid Generator

(canvas − 2 × outer margin − gutter × (columns − 1)) ÷ columns. The generator shows it to two decimal places, which is what Figma reports too.

Fluid, in almost every case. repeat(12, minmax(0, 1fr)) gives 12 equal columns that adapt to any container width. The fixed pixel value matters for your design file, not your CSS.

Because 1fr means minmax(auto, 1fr), and auto refuses to shrink below the content's intrinsic width. A long unbroken string then blows out the column. minmax(0, 1fr) lets it shrink properly.