very-simple-react-map/dist/components/Map.css

Basic OL3 map with osm layer wrapped in React Component

.map {
  display: flex;
  flex: 1;
  width: 350px;
  height: 250px;
  overflow: hidden;
  position: relative;
  margin-left: auto;
  margin-right: auto;
}

.map .target {
  position: absolute;
  top: 0;
  right: 0;
  bottom: 0;
  left: 0;
  height: 90%;
  padding: 10px;
  border: 1px solid black;
}