#entete, #menu {
    display: flex;
    flex: none;
    flex-direction: row;
    width : 100%;
}

#m1 {
    background-color: grey;
    color: black;
    text-align: center;
    height: 300px;
    width: 400px;
    padding: 5px;
    font-family: sans-serif;
}
#pied {
    width:100%;
#    position: absolute;
    text-align:center;
    bottom: 0;
    padding-top: 0px;
    padding-bottom: 10px;
    color: #ffffff;
    background: #000000;
    font-size: 75%;
}