.loading{
  width: 100%;
  height: 20px;
  margin: 9px auto;
  display: flex;
  justify-content: center;
}
.loading span{
  display: inline-block;
  width: 8px;
  height: 100%;
  border-radius: 4px;
  background: rgba(35,35,35,0.13);
  -webkit-animation: load 1s ease infinite;
}
@-webkit-keyframes load{
  0%,100%{
    height: 20px;
    background: rgba(35,35,35,0.13);
  }
  50%{
    height: 35px;
    margin: -8px 0;
    background: rgba(35,35,35,0.1);
  }
}
.loading span:nth-child(2){
  -webkit-animation-delay: 100ms;
}
.loading span:nth-child(3){
  -webkit-animation-delay: 280ms
}
.loading span:nth-child(4){
  -webkit-animation-delay: 440ms
}
.loading span:nth-child(5){
  -webkit-animation-delay: 600ms
}