col

A container that lays children out vertically. See row for the horizontal counterpart.

Attributes: gap=N, pad=N, align=start|center|end|stretch (cross-axis alignment; defaults to stretch).

Fill flags on a child claim the parent's free space: fill stretches in both directions, fillx only horizontally, filly only vertically. An explicit w=/h= always wins over stretching.

col gap=12 w=320
  heading "Stacked"
  text "Children flow top to bottom." muted
  button "Full width (stretch default)"
  row gap=8
    button "Cancel"
    spacer
    button "OK" primary