hard cutoff gradient

hr {
  background-image: -webkit-linear-gradient(left, #252525 0%, #252525 20%, #f5f5f5 20%, #f5f5f5 40%, #00b7b7 40%, #00b7b7 60%, #b70000 60%, #b70000 80%, #fcd50e 80%);
  height: 10px;
}