body {
    background-image: url(/bg.png)
}

header {
    margin: 0 auto;
    text-align: center;
    color: yellow;
}
header a {
    color: yellow;
}

h1, h2 {
    text-align: center;
}

main {
    margin: 0 auto;
    padding: 1em;
    max-width: 600px;
    background-color: white;
}

main img {
    max-width: 600px;
}