body {
  background: #000;
}
* {
  margin: 0;
  padding: 0;
}
ul, li{
  list-style: none;
}
ul{
  display: flex;
  gap: 2rem;
  padding: 12px;
  justify-content: center;
  flex-flow: wrap;
}
li{
  position: relative;
  width: 12px;
  height: 30px;
  background-color: yellow;
  border-radius: 10px;
  box-shadow: 0 2px 20px yellow;
  opacity: 1;
  animation: lighting 1s infinite;
}
li:before{
  position: absolute;
  content: '';
  width: 10px;
  height: 10px;
  border-radius: 5px;
  background-color: gray;
  z-index: 1;
  left: 1px;
  top: -5px;
  
}
li:after{
  position: absolute;
  content: '';
  height: 1px;
  width: 3rem;
  background-color: gray;
  z-index: -1;
  left: 1px;
  box-shadow: 0 2px 10px gray;
}
li:last-child:after{
  display: none;
}
li:nth-child(2n + 1) {
  background-color: green;
  box-shadow: 0 2px 20px green;
}
li:nth-child(3n + 1) {
  background-color: orangered;
  box-shadow: 0 2px 20px orangered;
}
@keyframes lighting {
  100%{
    opacity: 0.5;
  }
}