body {

  background: #E51C23;

}

​

.container {

  width: 80px;

  height: 100px;

  margin: 100px auto;

  margin-top: calc(100vh / 2 - 50px);

}

​

.block {

  position: relative;

  box-sizing: border-box;

  float: left;

  margin: 0 10px 10px 0;

  width: 12px;

  height: 12px;

  border-radius: 3px;

  background: #FFF;

}

​

.block:nth-child(4n+1) { animation: wave 2s ease .0s infinite; }

.block:nth-child(4n+2) { animation: wave 2s ease .2s infinite; }

.block:nth-child(4n+3) { animation: wave 2s ease .4s infinite; }

.block:nth-child(4n+4) { animation: wave 2s ease .6s infinite; margin-right: 0; }

​

@keyframes wave {

  0%   { top: 0;     opacity: 1; }

  50%  { top: 30px;  opacity: .2; }

  100% { top: 0;     opacity: 1; }

}