.sidebar-ad-left,
.sidebar-ad-right {
    display: none;
}

@media (min-width: 870px) {
    .sidebar-ad-left,
    .sidebar-ad-right {
        display: block !important;
        position: fixed !important;
        top: 180px;
        width: 120px;
        height: 600px;
        z-index: 10;
    }

    .sidebar-ad-left {
        left: calc(50% - 570px / 2 - 140px);
    }

    .sidebar-ad-right {
        right: calc(50% - 570px / 2 - 140px);
    }
}