vant-weapp/packages/loading/index.less

@import '../common/style/var.less';
@import '../common/style/theme.less';

:host {
  font-size: 0;
  line-height: 1;
}

.van-loading {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  .theme(color, '@loading-spinner-color');

  &__spinner {
    position: relative;
    box-sizing: border-box;
    .theme(width, '@loading-spinner-size');
    // compatible for 0.x, users may set width or height in root element
    max-width: 100%;
    max-height: 100%;
    .theme(height, '@loading-spinner-size');
    .theme(animation, 'van-rotate @loading-spinner-animation-duration linear infinite');

    &--spinner {
      animation-timing-function: steps(12);
    }

    &--circular {
      border: 1px solid transparent;
      border-top-color: currentColor;
      border-radius: 100%;
    }
  }

  &__text {
    .theme(margin-left, '@padding-xs');
    .theme(color, '@loading-text-color');
    .theme(font-size, '@loading-text-font-size');
    .theme(line-height, '@loading-text-line-height');

    &:empty {
      display: none;
    }
  }

  &--vertical {
    flex-direction: column;

    .van-loading__text {
      .theme(margin, '@padding-xs 0 0');
    }
  }

  &__dot {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;

    &::before {
      display: block;
      width: 2px;
      height: 25%;
      margin: 0 auto;
      background-color: currentColor;
      border-radius: 40%;
      content: ' ';
    }
  }
}

.generate(@n, @i: 1) when (@i =< @n) {
  .van-loading__dot:nth-of-type(@{i}) {
    transform: rotate(@i * 30deg);
    opacity: 1 - (0.75 / 12) * (@i - 1);
  }
  .generate(@n, (@i + 1));
}
.generate(12);

@keyframes van-rotate {
  from {
    transform: rotate(0deg);
  }

  to {
    transform: rotate(360deg);
  }
}