.main-box {
    margin-top: 20px;
    margin-bottom: 40px;
}

.mg-10 {
    margin-top: 10px;
    margin-bottom: 10px;
}

.mg-20 {
    margin-top: 20px;
    margin-bottom: 20px;
}

.row.middle-item > div {
    display: inline-block;
    vertical-align: middle;
    float: none;
}