body, html {
height: 100%;
}
.parallax {
/* The image used */ background-image: url('https://static.igem.org/mediawiki/2017/5/5e/Header.jpg');
/* Full height */ height: 100%;
/* Create the parallax scrolling effect */ background-attachment: fixed; background-position: center; background-repeat: no-repeat; background-size: cover;
}