Module tracks 

Hand parser for the grid strings the whitelist admits (from the VAPP-4 spike): gridTemplateColumns/Rows = <n>px | <n> | <n>% | <n>fr | auto | min-content | max-content | minmax(a, b) | repeat(n|auto-fill|auto-fit, …), gridTemplateAreas = string rows, gridArea = an area name, gridColumn/gridRow = a, a / b, span n, a name.

Functions

parse_area_placement

gridArea: "nav" → both axes span the named area.

parse_areas

gridTemplateAreas rows → named areas (1-based lines, end exclusive). . is an empty cell. Non-rectangular areas are rejected.

parse_placement

gridColumn / gridRow: "2", "1 / 3", "1 / -1", "span 2", "nav".

parse_tracks

gridTemplateColumns / gridTemplateRows.