html{
background-color: black;
text-align: left;
color: white;
font-size: 18px;
font-family: "Bookman Old Style";
}
body{

background-attachment:fixed;
}
div{
margin: auto;
width: 450px;
text-align: center;
border: 2px solid blue;
padding: 10px;
}
.couche{
text-align:center;
width:500px;
height:300px;
}
.underline{
text-decoration: underline;
}
.legende{
text-decoration:underline;
font-size:13px;
}
.auteur{
border: 1px solid red;
font-size: 10px;
}