html {
    background-color: ghostwhite;
}

body {
    background-color: white;
    max-width: 50em;
    margin: auto;
    padding-left: 2em;
    padding-right: 2em;
    padding-top: 1ex;
    padding-bottom: 3ex;
    border: 3px solid gray;
}

h1 {
    margin-top: 3ex;
    padding-top: 1ex;
    padding-left: 0.3em;
    border-top: 1px solid black;
}

figure img {
    margin-left: auto;
    margin-right: auto;
    display: block;
    max-width: 100%;
}

figure figcaption {
    text-align: center;
    margin-bottom: 5ex;
}

footer {
    margin-top: 5ex;
    padding-top: 1ex;
    border-top: 3px solid gray;
}