.comment::before {
    content: "";
    position: absolute;
    top: 40%;
    left: 0;
    border-style: solid;
    border-width: 8px 17px 8px 0;
    border-color: transparent rgba(0, 0, 0, 0.2) transparent transparent;
    translate: -100% -50%;
}
.comment::after {
    content: "";
    position: absolute;
    top: 40%;
    left: 0;
    border-style: solid;
    border-width: 7.8px 15.5px 7.8px 0;
    border-color: transparent #fff transparent transparent;
    translate: -100% -50%;
}