##Column layout with label
##boxcol column layout corner label nested
##A 'boxcol' is a block similar to 'box', but blocks inside it are laid out in a column, not a row.##You can define multiple boxes with one box keyword.##You can also add a label to blocks containing other blocks.
box A;
boxcol: Container [line.corner=round] {
    box B, C;
}
A -> B,C;

