Grow, shrink, basis
flex
This property sets the flexbox properties for flex-grow, flex-shrink and flex-basis.
Property values
This property is meaningful only on elements that are directly within a flexbox container.
See the separate specifications for each of the three individual property values.
Examples
/* flex-grow: 2; flex-shrink: 3; flex-basis: 100px; */
flex: 2 3 100px;