.lds-facebook {
  display: inline-block;
  position: relative;
    width: 50px;
    height: 46px;
}
.lds-facebook div {
  display: inline-block;
    position: absolute;
    left: 6px;
    width: 4px;
    background: #49acbe;
    animation: lds-facebook 1.2s cubic-bezier(0, 0.5, 0.5, 1) infinite;
}

.lds-facebook div:nth-child(1) {
  left: 6px;
  animation-delay: -0.48s;
}

.lds-facebook div:nth-child(2) {
  left: 18px;
  animation-delay: -0.24s;
}
.lds-facebook div:nth-child(3) {
  left: 30px;
  animation-delay: -0.12s;
}
.lds-facebook div:nth-child(4) {
  left: 42px;
  animation-delay: 0;
}
@keyframes lds-facebook {
  0% {
    top: 6px;
    height: 40px;
  }
  50%, 100% {
    top: 19px;
    height: 20px;
  }
}