SOURCE

<div class="loading">
    <i>
        <span></span>
        <span></span>
        <span></span>
        <span></span>
        <span></span>
        <span></span>
    </i>
</div>

html,
body,
div {
  margin: 0;
  padding: 0;
}

html,
body {
  width: 100%;
  height: 100%;
}

.loading {
  width: 100%;
  height: 100%;
  position: relative;
}

.loading i {
  margin: auto;
  position: absolute;
  top: calc(50% - 40px);
  left: calc(50% - 40px);
  width: 80px;
  height: 80px;
  display: block;
}

.loading span {
  position: absolute;
  width: 100%;
  height: 100%;
  opacity: 0;
}

.loading span:after {
  content: "";
  display: block;
  position: absolute;
  left: 0px;
  top: 0px;
  width: 10px;
  height: 10px;
  background: var(--main, #00baff);
  border-radius: 50%;
}

.loading span:nth-child(1) {
  animation: i1 5.5s 0.2s infinite;
}

.loading span:nth-child(2) {
  animation: i2 5.5s 0.4s infinite;
}

.loading span:nth-child(3) {
  animation: i3 5.5s 0.6s infinite;
}

.loading span:nth-child(4) {
  animation: i4 5.5s 0.8s infinite;
}

.loading span:nth-child(5) {
  animation: i5 5.5s 1s infinite;
}

.loading span:nth-child(6) {
  animation: i6 5.5s 1.2s infinite;
}

@keyframes i1 {
  0% {
    opacity: 1;
    transform: rotate(190deg);
    animation-timing-function: cubic-bezier(0.29, 0.44, 0.32, 0.74);
  }
  7% {
    opacity: 1;
    transform: rotate(300deg);
    animation-timing-function: linear;
  }
  30% {
    opacity: 1;
    transform: rotate(450deg);
    animation-timing-function: cubic-bezier(0.53, 0.27, 0.37, 0.81);
  }
  39% {
    opacity: 1;
    transform: rotate(645deg);
    animation-timing-function: linear;
  }
  63% {
    opacity: 1;
    transform: rotate(800deg);
    animation-timing-function: cubic-bezier(0.5, 0.32, 0.82, 0.54);
  }
  68% {
    opacity: 1;
    transform: rotate(920deg);
    animation-timing-function: ease-in;
  }
  69% {
    opacity: 0;
    transform: rotate(930deg);
  }
}
@keyframes i2 {
  0% {
    opacity: 1;
    transform: rotate(180deg);
    animation-timing-function: cubic-bezier(0.29, 0.44, 0.32, 0.74);
  }
  7% {
    opacity: 1;
    transform: rotate(300deg);
    animation-timing-function: linear;
  }
  30% {
    opacity: 1;
    transform: rotate(450deg);
    animation-timing-function: cubic-bezier(0.53, 0.27, 0.37, 0.81);
  }
  39% {
    opacity: 1;
    transform: rotate(645deg);
    animation-timing-function: linear;
  }
  63% {
    opacity: 1;
    transform: rotate(800deg);
    animation-timing-function: cubic-bezier(0.5, 0.32, 0.82, 0.54);
  }
  68% {
    opacity: 1;
    transform: rotate(910deg);
    animation-timing-function: ease-in;
  }
  69% {
    opacity: 0;
    transform: rotate(920deg);
  }
}
@keyframes i3 {
  0% {
    opacity: 1;
    transform: rotate(170deg);
    animation-timing-function: cubic-bezier(0.29, 0.44, 0.32, 0.74);
  }
  7% {
    opacity: 1;
    transform: rotate(300deg);
    animation-timing-function: linear;
  }
  30% {
    opacity: 1;
    transform: rotate(450deg);
    animation-timing-function: cubic-bezier(0.53, 0.27, 0.37, 0.81);
  }
  39% {
    opacity: 1;
    transform: rotate(645deg);
    animation-timing-function: linear;
  }
  63% {
    opacity: 1;
    transform: rotate(800deg);
    animation-timing-function: cubic-bezier(0.5, 0.32, 0.82, 0.54);
  }
  68% {
    opacity: 1;
    transform: rotate(900deg);
    animation-timing-function: ease-in;
  }
  69% {
    opacity: 0;
    transform: rotate(910deg);
  }
}
@keyframes i4 {
  0% {
    opacity: 1;
    transform: rotate(160deg);
    animation-timing-function: cubic-bezier(0.29, 0.44, 0.32, 0.74);
  }
  7% {
    opacity: 1;
    transform: rotate(300deg);
    animation-timing-function: linear;
  }
  30% {
    opacity: 1;
    transform: rotate(450deg);
    animation-timing-function: cubic-bezier(0.53, 0.27, 0.37, 0.81);
  }
  39% {
    opacity: 1;
    transform: rotate(645deg);
    animation-timing-function: linear;
  }
  63% {
    opacity: 1;
    transform: rotate(800deg);
    animation-timing-function: cubic-bezier(0.5, 0.32, 0.82, 0.54);
  }
  68% {
    opacity: 1;
    transform: rotate(890deg);
    animation-timing-function: ease-in;
  }
  69% {
    opacity: 0;
    transform: rotate(900deg);
  }
}
@keyframes i5 {
  0% {
    opacity: 1;
    transform: rotate(150deg);
    animation-timing-function: cubic-bezier(0.29, 0.44, 0.32, 0.74);
  }
  7% {
    opacity: 1;
    transform: rotate(300deg);
    animation-timing-function: linear;
  }
  30% {
    opacity: 1;
    transform: rotate(450deg);
    animation-timing-function: cubic-bezier(0.53, 0.27, 0.37, 0.81);
  }
  39% {
    opacity: 1;
    transform: rotate(645deg);
    animation-timing-function: linear;
  }
  63% {
    opacity: 1;
    transform: rotate(800deg);
    animation-timing-function: cubic-bezier(0.5, 0.32, 0.82, 0.54);
  }
  68% {
    opacity: 1;
    transform: rotate(880deg);
    animation-timing-function: ease-in;
  }
  69% {
    opacity: 0;
    transform: rotate(880deg);
  }
}
@keyframes i6 {
  0% {
    opacity: 1;
    transform: rotate(140deg);
    animation-timing-function: cubic-bezier(0.29, 0.44, 0.32, 0.74);
  }
  7% {
    opacity: 1;
    transform: rotate(300deg);
    animation-timing-function: linear;
  }
  30% {
    opacity: 1;
    transform: rotate(450deg);
    animation-timing-function: cubic-bezier(0.53, 0.27, 0.37, 0.81);
  }
  39% {
    opacity: 1;
    transform: rotate(645deg);
    animation-timing-function: linear;
  }
  63% {
    opacity: 1;
    transform: rotate(800deg);
    animation-timing-function: cubic-bezier(0.5, 0.32, 0.82, 0.54);
  }
  68% {
    opacity: 1;
    transform: rotate(870deg);
    animation-timing-function: ease-in;
  }
  69% {
    opacity: 0;
    transform: rotate(880deg);
  }
}