.paper-canvas {
    /* top: 1px; /* leave room for the border */
    /* left: 1px;
    width: calc(100% - 2px);
    height: calc(100% - 2px); */
    width: 480px;
    height: 360px;
    margin: auto;
    position: absolute;
    background-color: #D9E3F2;
}