body {
    font-family: 'JetBrains Mono', monospace;
    background-color: beige;
}

img {
    display: block;
    margin-left: auto;
    margin-right: auto;
}

/* This is from your existing file, which is a good reset */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

.content {
    text-align: center;
    max-width: 600px;
    margin: 0 auto 40px;
}