div.card, div.button {
    max-width: 950px;
    height: 25%;
    text-align: center;
    display: flex;
    align-items: center;
    border-radius: 18px;
    margin: 4px auto;
    user-select: none;
    font-size: 3vh;
    font-weight: 600;
}
html {
    background: #212326;
}
body {
    margin:0;
}
span {
    width: 100%;
    padding: 10px;
}
div.front {
    background: #2e3136;
    color: white;
}
div.back {
    background: #878b97;
    color: black;
}
div.next {display:none;}
div.back span {
    display: none;
}
div.button {
    background: #696f75;
    color: white;
}
div.button:active {
    background:#2e3136;
    color:white;
}
div.sections,
div.units {
    display: flex;
}
h1.title {
    text-align: center;
    color: #738bd7;
    font-size: 2.5vh;
    margin: 5px 0;
}
span#detail {
    font-size: 1.5vh;
}
div#details {
    display:none;
    margin: 10px 21px 21px;
}
div#details dt {
    color: #696f75;
    font-weight: bold;
    margin-top: 8px;
}
div#details dd {
    color: #878b97;
}
a.section {
    display: block;
    padding: 5px;
    font-size: 3vh;
    text-align: center;
    width: -moz-available;          /* WebKit-based browsers will ignore this. */
    width: -webkit-fill-available;  /* Mozilla-based browsers will ignore this. */
    width: fill-available;
    color: #738bd7;
    text-decoration: none;
    background: #2e3136;
    border-radius: 5px;
    margin: 0 2px;
}
a.section.selected {
    color: white;
}