body {
    margin: 0;
    padding: 0;
    color: rgba(255, 255, 255, 0.87);
    background-color: #000000;
    -webkit-user-select: none; /* Safari */
    -ms-user-select: none; /* IE 10 and IE 11 */
    user-select: none; /* Standard syntax */
}

#app {
    width: 100%;
    height: 100vh;
    overflow: hidden;
    display: flex;
    justify-content: center;
    align-items: center;
    -webkit-user-select: none; /* Safari */
    -ms-user-select: none; /* IE 10 and IE 11 */
    user-select: none; /* Standard syntax */
}