body {
    background-color: black;
    margin: 0;
    padding: 0;
}

body main {
    width: 100vw;
    height: 100vh;
    /* background: url('../img/Site_en_cours_de_construction.jpg') no-repeat center center fixed; 
    -webkit-background-size: cover;
    -moz-background-size: cover;
    -o-background-size: cover;
    background-size: cover; */
    display: flex;
    align-items: center;
}

body main img {
    width: 100%;
    height: auto;
}