html, body {
    margin: 0;
    padding: 0;
    height: 100%;
}

body {
    display: flex;
    background: #111;
}

main {
    position: relative;
    display: flex;
    justify-content: center;
    align-items: center;
    margin: auto;
}

canvas {
    background: black;
}

#notice, #caption {
    position: absolute;
    font-family: sans-serif;
    font-size: 2.5vw;
    color: white;
    white-space: pre-line;
    background: rgba(0, 0, 0, 0.5);
}

#notice {
    display: block;
}

#caption {
    display: inline-block;
    bottom: 10px;
    margin: auto;
    padding: 10px;
}