h1 {
    text-align: center;
}

main {
    width: 50vw;
    height: 50vh;
    display: flex;
    justify-content: space-evenly;
    margin-left: auto;
    margin-right: auto;
}

div {
    flex: 1 1 50%;
}

img {
    height: 66%;
    width: auto;
    flex: none;
}