Alignment subject
In CSS box alignment the alignment subject is the thing (or things) being aligned by the property.
For justify-self and align-self, the alignment subject is the margin box of the box the property is set on, using the writing mode of that box. For justify-content and align-content, the writing mode of the box is also used.
The definition of the alignment subject depends on the layout mode being used.
- Block containers (including table cells)
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The entire content of the block as a single unit.
- Multicol containers
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The column boxes, with any spacing inserted between column boxes added to the relevant column gaps.
- Flex containers
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For
justify-content, the flex items in each flex line. Foralign-content, the flex lines. Note, this only has an effect on multi-line flex containers. - Grid containers
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The grid tracks in the appropriate axis, with any spacing inserted between tracks added to the relevant gutters. Collapsed gutters are treated as a single opportunity for space insertion.
See also
- CSS box alignment module