flex: 0 0 200px;

Lorem ipsum dolor sit amet, consectetuer adipiscing elit.

flex: 4 1 auto;

Lorem ipsum dolor sit amet, consectetuer adipiscing elit. Lorem ipsum dolor sit amet, consectetuer adipiscing elit.

flex: 1 3 150px;

Lorem ipsum dolor sit amet, consectetuer adipiscing elit. Lorem ipsum dolor sit amet, consectetuer adipiscing elit.