我可以在纯css滑块中添加点吗？

.slider {
  position: relative;
  width: 200px;
  height: 10px;
  background-color: #ccc;
}

.slider:before {
  content: "";
  position: absolute;
  top: -5px;
  left: 0;
  width: 10px;
  height: 10px;
  background-color: #f00;
  border-radius: 50%;
}

.slider:after {
  content: "";
  position: absolute;
  top: -5px;
  right: 0;
  width: 10px;
  height: 10px;
  background-color: #f00;
  border-radius: 50%;
}