.cadre {
    top:50%;left:50%;
    position:absolute;
    width:800px;height:600px;
    margin-left:-400px;
    margin-top:-300px;
    object-fit: scale-down;
    background-image: url(nuit_jeumoon1000.png);
    background-position:center center;
    background-repeat: no-repeat;
    background-size: cover;  
    }

    #moon {
    top:70px;left:130px;
    width:135px;height:135px;
    background-image: url(moon_4.png);
    background-position:center center;
    background-repeat: no-repeat;
    background-size: cover;  
    }