body, html {
    margin: 0;
    padding: 0;
    height: 100%;
    overflow: hidden;
    user-select: none;
    touch-action: manipulation;
    background-color: #f0f0f0;
}

/* --- LES CANVASES --- */
canvas {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
}

#imageCanvas {
    z-index: 1; /* Tout au fond */
    background-color: white;
    background-size: contain;
    background-repeat: no-repeat;
    background-position: center;
}

#drawingCanvas {
    z-index: 5; /* Au milieu */
    background-color: transparent !important;
    pointer-events: auto; 
}

/* --- L'INTERFACE (Boutons et Menus) --- */
.bottom-buttons {
    z-index: 100 !important; /* Devant les canvas */
    position: fixed;
}

.list-overlay {
    z-index: 200 !important; /* Devant tout le reste */
}

#user-management {
    z-index: 300; /* Toujours visible en haut */
}

/* Correction pour les clics sur les couleurs */
.list-itemColor {
    cursor: pointer;
    pointer-events: auto !important;
}