/* Conteneur principal */
#container {
    position: relative;
    width: 200px;
    height: 300px;  
    overflow:hidden;
    background-color: #cce5ff;
}

/* Fenêtres déplaçables */
.window {
    position: absolute;
    width: 80px; 
    height: 100px;
    border: 1px solid black;
    cursor: move;
    background-size: cover;
    background-position: center;
    transition: z-index 0.3s; 
}