framework/less/common/LoadingIndicator.less

// ------------------------------------
// Loading Indicators

.LoadingIndicator {
  @spin-time: 750ms;

  // Use the value of `color` to maintain backwards compatibility
  border-color: currentColor;
  border-width: var(--thickness);
  border-style: solid;
  border-top-color: transparent;
  border-radius: 50%;

  width: var(--size);
  height: var(--size);

  animation: spin @spin-time linear infinite;

  // <div> container around the spinner
  // Used for positioning
  &-container {
    --size: 24px;
    --thickness: 2px;

    color: @muted-color;

    // Center vertically and horizontally
    // Allows people to set `height` and it'll stay centered within the new height
    display: flex;
    align-items: center;
    justify-content: center;

    // Size

    &--large {
      --size: 32px;
      --thickness: 3px;
    }

    &--small {
      --size: 18px;
    }

    // Display types

    &--block {
      height: 100px;
    }

    &--inline {
      display: inline-block;
      vertical-align: middle;
    }
  }
}

@keyframes spin {
  from {
    transform: rotate(0);
  }

  to {
    transform: rotate(1turn);
  }
}