[csswg-drafts] [css-backgrounds] Order of values for border shorthands is unclear (#5100)

zjopy has just created a new issue for https://github.com/w3c/csswg-drafts:

== [css-backgrounds] Order of values for border shorthands is unclear ==
The definitions of the order of values for the shorthands `border-color`, `border-style` and `border-width` seem a bit unclear. For all three the [spec](https://www.w3.org/TR/css-backgrounds-3/#the-border-color) states

> If it has four values, they set top, right, bottom and left in that order. If left is missing, it is the same as right; if bottom is missing, it is the same as top; if right is missing, it is the same as top.

So what happens with three or two values, e.g. `border-width: a b c` or `border-width: a b`? How does it know which side I left out?

By trial and error I know the order is the same as for the `margin` and `padding` shorthands. The definitions of `margin` and `padding` are much clearer though. The [spec](https://www.w3.org/TR/css-box-4/#margin-shorthand) states

> If there is only one component value, it applies to all sides. If there are two values, the top and bottom (padding) are set to the first value and the right and left (padding) are set to the second. If there are three values, the top is set to the first value, the left and right are set to the second, and the bottom is set to the third.

I would suggest taking over this part of the definition from `margin` / `padding` for the border properties as well.

Please view or discuss this issue at https://github.com/w3c/csswg-drafts/issues/5100 using your GitHub account

Received on Friday, 22 May 2020 09:01:11 UTC