body {
    position: fixed;
    top: 0; bottom: 0; left: 0; right: 0;
    margin: auto;
    overflow: auto !important;
    -webkit-overflow-scrolling: touch !important;
}

.post-text h2 {
    font-size: 25px;
}

.post-text h3 {
    font-size: 22px;
}