Who Counts as a Flex Item?

.crew is the flex container. Each direct child is a flex item. The nested label is not.

Direct child · flex item Nested inside · not a flex item
Alpha
flex item
Bravo
flex item
Wrapper
flex item
nested · not a flex item
Delta
flex item

One container with display: flex, four direct children as flex items, and a nested element that stays outside the flex item club. Every future flexbox rule will talk to this group.