CSS arrow without with shadow/borders

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.tago-infobox-arrow {
    position: absolute;
    width: 32px;
    height: 32px;
    left: 50%;
    margin-left: -16px;
    bottom: -32px;
    overflow: hidden;

    &:before {
        content: '';
        position: absolute;
        width: 16px;
        height: 16px;
        top: -8px;
        left: 8px;

        background-color: #fff;
        box-shadow: 0px 0px 1px 1px rgba(0,0,0,.2);

        transform: rotate(45deg);
    }
}