- From: Bert Bos <Bert.Bos@sophia.inria.fr>
- Date: Wed, 12 Aug 1998 16:07:38 +0200 (MET DST)
- To: <braden@endoframe.com>
- Cc: "W3C Style Sheets Mailing List (E-mail)" <www-style@w3.org>
Braden N. McDaniel writes:
> The description of list-style-position says:
>
> "This property specifies the position of the marker box in the principal
> block box."
>
> Referring to section 9.2.1:
>
> "Block-level elements generate a principal block box that only contains
> block boxes. The principal block box establishes the containing block for
> descendant boxes and generated content and is also the box involved in any
> positioning scheme."
>
> I'm trying to establish where the boundary of the principal block box should
> be. My interpretation from this is that it is the outer extremity of the
> margin. Is that accurate?
The "principal box" is not defined as a rectangle. It refers to a box
generated by a block object as a whole, not to any of that box's edges
in particular.
>
> The description of list-style-position goes on to describe the behavior of
> the "outside" value:
>
> "The marker box is outside the principal block box. ..."
>
> Does this mean that "outside" specifies that the marker should be outside
> the margin of the list item?
Not necessarily.
There is more info in 12.6.1 "Markers: the 'marker-offset' property":
"The 'marker-offset' property specifies the horizontal offset between
a marker box and the associated principal box. The distance is
measured between their nearest border edges."
So, "outside" should be interpreted as "outside the border."
+-----------------------------M-------+
+-----B--------+ | +---------------------------B-----+ |
| +---P------+ | marker- | | +-------------------------P---+ | |
| | +-C----+ | | offset | | | +-----------------------C-+ | | |
| | |marker| | |<==========>| | |principal box | | | |
| | +------+ | | | | | | | | | |
| +----------+ | | | | | | | | |
+--------------+ | | | | | | | |
| | | | | | | |
| | | | | | | |
| | | | | | | |
M = margin edge | | | | | | | |
B = border edge | | | +-------------------------+ | | |
P = padding edge | | +-----------------------------+ | |
C = content edge | +---------------------------------+ |
+-------------------------------------+
If 'marker-offset' is 'auto' (the initial value), the UA is free to
choose a suitable offset.
Bert
--
Bert Bos ( W 3 C ) http://www.w3.org/
http://www.w3.org/people/bos/ W3C/INRIA
bert@w3.org 2004 Rt des Lucioles / BP 93
+33 (0)4 92 38 76 92 06902 Sophia Antipolis Cedex, France
Received on Wednesday, 12 August 1998 10:08:13 UTC