Loading spinner in pure css

<div class="spinner">
  <div></div>
  <div></div>
  <div></div>
  <div></div>
  <div></div>
  <div></div>
</div>

.spinner {
  --radius:4rem;
  --bar_length:1rem;
  --bar_thickness:0.35rem;
  --bar_border_radius:5px;
  --speed: 0.1s;
  --bar_color:dodgerblue;

  height: var(--radius);
  width: var(--radius);
  position: relative;
  display: flex;
  justify-content: center;
  align-items: center;
}

.spinner div {
  position: absolute;
  display: flex;
  justify-content: center;
  height: 100%;
}

.spinner div::before, 
.spinner div::after {
    content: '';
    display: block;
    height: var(--bar_length);
    width: var(--bar_thickness);
    background-color: var(--bar_color);
    position: absolute;
    border-radius:var(--bar_border_radius);
    animation: spinning calc(var(--speed) * 12) linear infinite;
  }

.spinner div::after{
  bottom: 0;
}

.spinner div:nth-child(1) {
  transform: rotate(-30deg);
}
.spinner div:nth-child(1)::before {
  animation-delay: calc(var(--speed) * -7);
}
.spinner div:nth-child(1)::after {
  animation-delay: calc(var(--speed) * -1);
}
.spinner div:nth-child(2) {
  transform: rotate(-60deg);
}
.spinner div:nth-child(2)::before {
  animation-delay: calc(var(--speed) * -8);
}
.spinner div:nth-child(2)::after {
  animation-delay: calc(var(--speed) * -2);
}
.spinner div:nth-child(3) {
  transform: rotate(-90deg);
}
.spinner div:nth-child(3)::before {
  animation-delay: calc(var(--speed) * -9);
}
.spinner div:nth-child(3)::after {
  animation-delay: calc(var(--speed) * -3);
}
.spinner div:nth-child(4) {
  transform: rotate(-120deg);
}
.spinner div:nth-child(4)::before {
  animation-delay: calc(var(--speed) * -10);
}
.spinner div:nth-child(4)::after {
  animation-delay: calc(var(--speed) * -4);
}
.spinner div:nth-child(5) {
  transform: rotate(-150deg);
}
.spinner div:nth-child(5)::before {
  animation-delay: calc(var(--speed) * -11);
}
.spinner div:nth-child(5)::after {
  animation-delay: calc(var(--speed) * -5);
}
.spinner div:nth-child(6) {
  transform: rotate(-180deg);
}
.spinner div:nth-child(6)::before {
  animation-delay: calc(var(--speed) * -12);
}
.spinner div:nth-child(6)::after {
  animation-delay: calc(var(--speed) * -6);
}


@keyframes spinning{
  0% {
    opacity: 1;
  }
  100% {
    opacity: 0;
  }
}

$radius: 4rem;
$bar_color: dodgerblue;
$bar_length: 1rem;
$bar_thickness: 0.35rem;
$bar_border_radius: 5px;
$speed: 0.1s;

.spinner {
  height: $radius;
  width: $radius;
  display: flex;
  justify-content: center;
  align-items: center;
  position: relative;

  div {
    position: absolute;
    display: flex;
    justify-content: center;
    height: 100%;

    &::before, &::after {
      content: '';
      display: block;
      height: $bar_length;
      width: $bar_thickness;
      background-color: $bar_color;
      position: absolute;
      border-radius:$bar_border_radius;
      animation: spinning $speed*12 linear infinite;
    }

    &::after{
      bottom: 0;
    }

    @for $i from 1 through 6 {
      &:nth-child(#{$i}) {
        transform: rotate(-30deg * $i);
        
        &::before{
          animation-delay: $speed * ($i + 6) * -1;
        }
        
        &::after{
          animation-delay: $speed * $i * -1;
        }
      }
    }

  }
}


@keyframes spinning{
  0% {
    opacity: 1;
  }
  100% {
    opacity: 0;
  }
}