openlayers/examples/raster.css

.rel {
  position: relative
}

#plot {
  pointer-events: none;
  position: absolute;
  bottom: 10px;
  left: 10px;
}

.bar {
  pointer-events: auto;
  fill: #AFAFB9;
}

.bar.selected {
  fill: green;
}

.tip {
  position: absolute;
  background: black;
  color: white;
  padding: 6px;
  font-size: 12px;
  border-radius: 4px;
  margin-bottom: 10px;
  display: none;
  opacity: 0;
}