lens/src/renderer/components/spinner/spinner.scss

.Spinner {
  --spinner-size: 24px;
  --spinner-border: calc(var(--spinner-size) / 6);

  $duration: 1s;
  $rotateAnimation: rotate $duration linear infinite;
  $colorAnimation: colors $duration*4 ease-in-out infinite;

  @mixin spinner-color($color) {
    border-color: transparent $color;
  }

  width: var(--spinner-size);
  height: var(--spinner-size);
  border: var(--spinner-border) solid transparent;
  border-radius: 50%;
  display: inline-block;

  &:not(.singleColor) {
    animation: $rotateAnimation, $colorAnimation;
  }

  &.singleColor {
    @include spinner-color($textColorPrimary);
    animation: $rotateAnimation;
  }

  &.center {
    position: absolute;
    left: 50%;
    top: 50%;
    margin-left: calc(var(--spinner-size) / -2);
    margin-top: calc(var(--spinner-size) / -2);
  }

  @keyframes rotate {
    0% {
      transform: rotate(0deg);
    }
    100% {
      transform: rotate(360deg);
    }
  }

  @keyframes colors {
    0% {
      @include spinner-color(#4285F4);
    }
    25% {
      @include spinner-color(#DE3E35);
    }
    50% {
      @include spinner-color(#F7C223);
    }
    75% {
      @include spinner-color(#1B9A59);
    }
    100% {
      @include spinner-color(#4285F4);
    }
  }
}