The flex items are laid out in a single line which may cause the flex container to overflow. The cross-start is either equivalent to start or before depending flex-direction value.
wrap
The flex items break into multiple lines. The cross-start is either equivalent to start or before depending flex-direction value and the cross-end is the opposite of the specified cross-start.
wrap-reverse
Behaves the same as wrap but cross-start and cross-end are permuted.