One union serves alignItems, alignSelf and alignContent, carrying the union
of what the three accept rather than their intersection: the space-* values
belong to alignContent alone, and baseline to the other two. There is no
auto: a property left unset is what defers to the parent, so absence says it
and a value cannot.
Placement along the cross axis.
One union serves
alignItems,alignSelfandalignContent, carrying the union of what the three accept rather than their intersection: thespace-*values belong toalignContentalone, andbaselineto the other two. There is noauto: a property left unset is what defers to the parent, so absence says it and a value cannot.