html, body, .main {
    height: 100%;
}

.main {
    display: -webkit-flexbox;
    display: -ms-flexbox;
    display: -webkit-flex;
    display: flex;
    -webkit-flex-align: center;
    -ms-flex-align: center;
    -webkit-align-items: center;
    align-items: center;
    justify-content: center;
}

.logo {
    margin-bottom: 64px;
}