.cube-loading-spinner {
    position: absolute;
    left: 44.5%;
    top: 37%;
    width: 2px; // for rem
    height: 25%;
    border-radius: 50%/20%;
    opacity: 0.25;
    background-color: currentColor;
    animation: spinner-fade 1s linear infinite;

    @for $i from 1 through 12 {
        &:nth-child(#{$i}) {
            animation-delay: (($i - 1) / 12)s;
            transform: rotate(30deg * ($i - 6)) translateY(-150%);
        }
    }
}

有多余空格，如何解决