.frame
	.center
		- for i in (1..20)
			div class="dot dot-#{i}" style="--index: #{i}"
View Compiled
.frame {
  position: absolute;
  top: 50%;
  left: 50%;
  width: 400px;
  height: 400px;
  margin-top: -200px;
  margin-left: -200px;
  border-radius: 2px;
	box-shadow: 4px 8px 16px 0 rgba(0,0,0,0.1);
	overflow: hidden;
  background: #fff;
  color: #333;
	font-family: 'Open Sans', Helvetica, sans-serif;
	-webkit-font-smoothing: antialiased;
	-moz-osx-font-smoothing: grayscale;
		background: #4c4ba2;
}

.center {
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%,-50%);

}

.center > div {
	--time: calc(60 / calc(40 + 20 - var(--index)) * 1000ms);
	height: 10px;
	width: 10px;
	background:  white;
	margin-bottom: 7px;
	border-radius: 100%;
	animation: dot var(--time) ease-in-out infinite;
}

@keyframes dot {
	0%, 100% {
		transform: translateX(50px);
	}
	50% {
		transform: translateX(-50px);
	}
}

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