#progress-bar {
  width: 100%;
  background: #ddd;
  height: 30px;
  position: relative;
  border-radius: 5px;
}
#progress-bar span {
  display: block;
  height: 100%;
  background: #4caf50;
  color: #fff;
  text-align: center;
  width: 0%;
  line-height: 30px;
  border-radius: 5px;
}