html{
    font-size: 25px;
}
body{
    background-color: white;
    margin:0%;
    width:100%;
}
.titre{
    color:black;
    font-size:3rem;
    text-align: center;
    font-weight: bolder;
}
.titresecondaire{
    color:black;
    font-size: 2.5rem;
    text-align: center;
    font-weight: bold;
}
.photo{
    display:block;
    margin:0 auto;
    box-sizing: border-box;
    font-size: 2rem;
    text-align: center;
}
.photo img {
    display: block;
    margin: 0 auto;       /* centre l’image */
}