ISSUE-141: baseline of an inline-box

baseline of an inline-box

CSS3 Flexbox
Raised by:
Alex Mogilevsky
Opened on:

Where is the baseline of an inline-box?

Option 1:
Baseline of the first flex item, in markup order, in ordinal group with smallest index (in all orientations, directions and alignments)
Similar to inline-table: "The baseline of an 'inline-table' is the baseline of the first row of the table. " (CSS2.1-10.8.1)

Option 2:
Vertical orientation:
Baseline of the first flex item.

Horizontal orientation:
Baseline alignment: the baseline used for alignment.
All other alignments: the bottom margin edge.

Option 3:
Similar to inline-block:
"The baseline of an 'inline-block' is the baseline of its last line box in the normal flow, unless it has either no in-flow line boxes or if its 'overflow' property has a computed value other than 'visible', in which case the baseline is the bottom margin edge." (CSS2.1-10.8.1)
(this may make sense for a single-item flexbox but not sure how to extend this similarity to multiple items)

option 1
Related Actions Items:
No related actions
Related emails:
  1. Re: [css3-flexbox] Flexbox needs to define where the baseline of a box is (from on 2011-02-23)
  2. [CSSWG] Minutes and Resolutions Oslo F2F 2010 Tuesday: GCPM, MQ, Flexbox, Multicol, box-shadow, Publications, Future F2Fs (from on 2010-08-31)
  3. Re: [css3-flexbox] issues resolved in FTF (from on 2010-08-25)
  4. [css3-flexbox] issues resolved in FTF (from on 2010-08-25)
  5. ISSUE-141: baseline of an inline-box (from on 2010-08-23)

Related notes:

Baseline of a flexbox is the baseline of its first child (in source order, in the first ordinal group). This doesn’t depend on direction, orientation or ‘box-lines’ property.
NOTE: this simple rule may need to be adjusted if use cases are found where getting baseline from the first child is not the best choice. To be updated as needed.

Within a flexbox, baselines of children are determined in the same way as when applying baseline alignment to table cells (baseline of an element with multiple lines of text is the baseline of its first line).

(option 1)

Alex Mogilevsky, 25 Aug 2010, 09:17:16


Elika Etemad, 19 Jan 2013, 01:18:06

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