SOURCE

<div class="main">
  <div class="loader">
    <span></span>
    <span></span>
    <span></span>
    <span></span>
    <span></span>
    <span></span>
    <span></span>
    <span></span>
    <span></span>
  </div>
</div>

body {
  margin: 0;
  height: 100vh;
  /* padding-top: 20px; */
  display: flex;
  align-item: center;
  justify-content: center;
  background-color: #000;
}

.main {
  padding: 80px 20px;
}

.loader {
  width: 10em;
  height: 10em;
/*   border: 1px dashed #fff; */
  font-size: 25px;
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  grid-gap: 0.5em;
/*   counter-reset: number; */
  transform: rotate(45deg);
}

.loader span {
  background-color: var(--color);
/*   position: relative; */
  animation: blinking 2s linear infinite;
  transform: scale(0);
  animation-delay: var(--delay);
}
@keyframes blinking {
  0%, 100% { transform: scale(0); }
  40%, 80% { transform: scale(1); }
}

.loader span::before {
  /* counter-increment: number; */
  /* content: counter(number); */
  /* color: #fff; */
  /* position: absolute; */
  /* width: 100%; */
  /* height: 100%; */
  /* text-align: center; */
  /* line-height: 3em; */
  /* transform: rotate(-45deg); */
}
 
.loader span:nth-child(7) {
  --color: #419693;
  --delay: 0s;
}
.loader span:nth-child(4),
.loader span:nth-child(8) {
  --color: #4fb7b4;
  --delay: 0.2s;
}
.loader span:nth-child(1), 
.loader span:nth-child(5),
.loader span:nth-child(9) {
  --color: #93d6d0;
  --delay: 0.4s;
}
.loader span:nth-child(2),
.loader span:nth-child(6) {
  --color: #4fb7b4;
  --delay: 0.6s;
}
.loader span:nth-child(3) {
  --color: #419693;
  --delay: 0.8s;
}