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Re: [css21] Collapsing margins

From: Andrew Fedoniouk <news@terrainformatica.com>
Date: Sat, 18 Feb 2006 22:43:38 -0800
Message-ID: <00f801c6351f$d0dde860$3201a8c0@Terra>
To: "Kelly Miller" <lightsolphoenix@gmail.com>
Cc: <www-style@w3.org>

Thanks, Kelly,

----- Original Message ----- 
From: "Kelly Miller" <lightsolphoenix@gmail.com>
To: "Andrew Fedoniouk" <news@terrainformatica.com>
Cc: <www-style@w3.org>
Sent: Saturday, February 18, 2006 9:16 PM
Subject: Re: [css21] Collapsing margins


>
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> The spec is referring to situations where the bottom margin of one block
> is right up against the top margin of the next block.  Collapsing can
> also occur if a parent element has no padding or borders and the
> first/last child has margins of its own (then the child's margins would
> collapse with the parents).

You are speaking about two boxes but [css21] is
using singular form:  "a box":

"If the top and bottom margins of a box are adjoining, then it is
possible for margins to collapse through it."

So it could be literally read as:
"margins of a zero height box may collapse through it"

Is this a meaning of the phrase? collapse through what?


Andrew Fedoniouk.
http://terrainformatica.com



>
> And yes, what you describe is also a collapsing condition (if a block
> element has no height, then it's top and bottom margins will collapse
> together, and possibly with the margins of the blocks above/below it).
>
> Andrew Fedoniouk wrote:
> |
> | Can anybody comment following [1]:
> |
> | <quote>
> | If the top and bottom margins of a box are adjoining, then it is
> | possible for margins to collapse through it. In this case, the position
> | of the element depends on its relationship with the other elements whose
> | margins are being collapsed. </quote>
> |
> | What exactly means: "top and bottom margins of a box are adjoining"? Top
> | and bottom margins of a box are adjacent to each other?
> |
> | If yes then there is only one case when it is possible - when block has
> | computed value of height equals to zero.
> |
> | And also "then it is possible" implies some indetermination.
> | Is this the intention?
> |
> | OT: Is it possible in principle to define margin collapsing in terms of
> | :first-child or something like this?
> |
> | Andrew Fedoniouk.
> | http://terrainformatica.com
> |
> |
> | [1]  http://www.w3.org/TR/CSS21/box.html#collapsing-margins
> |
> |
>
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Received on Sunday, 19 February 2006 06:43:53 GMT

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