https://drafts.csswg.org/css-multicol-2/#columns

The value of columns is currently defined as:

Value: <'column-width'> || <'column-count'> || <'column-height'> || <'column-wrap'>

I.e. four longhand properties in any order.

This won't work, since there are two length values (column-width and column-height), so the order would have to be specified.

At the same time, ever since the introduction of multicol, we've been allowed to do column-count and column-width in any order, so this has to be kept.

Maybe we need a '/' in the syntax, and place column-height in the denominator? Or some sort of intricate syntax to allow column-width and column-height in any order (at least if they're the two first values), but not the rest. In any case, if the author only wants to specify column height, the shorthand will not be super-pretty. auto / <column-height>? auto auto auto <column-height>?

@rachelandrew