html, body {
    width: 100%;
    height: 100%;
}
body {
    margin: 0;
    background: whitesmoke;
    color: #444;
    font-family: monospace;
}
#app-container {
    max-width: 1150px;
    height: 100%;
    margin: 0 auto;
    display: flex;
}
#app {
    width: 100%;
    height: 100%;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
}