em {
    color: #800;
}
.reveal section img {
    box-shadow: 0 0 10px #0008;
    background:none;
    border:none;
}
.reveal img {
/*    max-height: 50vh;*/

}
section[data-wider] {
    width:120% !important;
    margin-left:-10% !important;
}
section[data-smaller] {
    font-size:smaller
}
section[data-flushleft] {
    text-align: left
}
section[data-flushleft] h1, section[data-flushleft] h2, section[data-flushleft] h3, section[data-flushleft] h4, section[data-flushleft] h5, section[data-flushleft] h6 {
    text-align: center
}
.columns {
    display: flex;
    justify-content: center;
}

.columns > * {
    flex: 1;
}

.columns > img {
    flex-shrink:2;
}