header {
    justify-content: center;
}

html {
    background: url('../assets/background-503.jpg') no-repeat center center fixed; 
    -webkit-background-size: cover;
    -moz-background-size: cover;
    -o-background-size: cover;
    background-size: cover;
}

main h1 {
    text-align: center;
    font-size: 75px;
    margin: 1em;
    color: #fad55c;
    text-shadow: 2px 2px 1px #9edd56;
}