@patternfly/react-core/src/layouts/Stack/examples/stack.css

This library provides a set of common React components for use with the PatternFly reference implementation.

.ws-react-l-stack {
  min-height: 30em;
  display: flex;
  flex-direction: column;
}

.ws-react-l-stack > .pf-l-stack {
  flex-grow: 1;
}

.ws-react-l-stack .pf-l-stack,
.ws-react-l-stack .pf-l-stack > .pf-l-stack__item {
  padding: 1rem;
  border-width: 2px;
  border-style: dashed;
}