.customize-control-mt-divider {
    hr {
        margin-top: 12px;
    }
    .customize-control-title {
        font-size: 15px;
        margin: 1em 0 0.2em;
    }
}

.customize-control-mt-divider {
    background-color: #f5f5f5;
    display: block;
    padding: 6px 14px;
    margin: 0;
    border-width: 1px 0;
    border-style: solid;
    border-color: #dddddd;
    line-height: 1;
    margin-top: 15px;
}