@for $i from 0 through 16 {
  .loader-item:nth-child(#{$i}) {
    @if $i % 2 == 0 {
      animation-delay: #{$i * 50 * random(5)}ms;
      animation-direction: reverse;
    } @else {
      animation-delay: #{$i * -50 * random(5)}ms;
      animation-direction: alternate;
    }
  }
}
.loader-item {
  animation: flickering 0.4s linear alternate infinite;
}
@keyframes flickering {
  0% {
    opacity: 1;
  }
  25% {
    opacity: 1;
  }
  26% {
    opacity: 0;
  }
  100% {
    opacity: 0;
  }
}
