html {
    /* background: url("https://github.com/heincm/react-game/blob/master/public/images/marvel_background.jpeg?raw=true") no-repeat center center fixed; */
    -webkit-background-size: cover;
    -moz-background-size: cover;
    -o-background-size: cover;
    background-size: cover;
    color: #000;
}
body {
    background: url("https://github.com/heincm/react-game/blob/master/public/images/marvel_background.jpeg?raw=true") no-repeat center center fixed;
    -webkit-background-size: cover;
    -moz-background-size: cover;
    -o-background-size: cover;
    background-size: cover;
    color: #000;
}