html,
body {
    width: 100vw;
    height: 100vh;
}

body {
    display: grid;
    grid-template-columns: minmax(0, 1fr);
    grid-template-rows: minmax(0, 1fr);
    width: 100vw;
    height: 100vh;
}

.container {
    align-self: center;
    justify-self: center;
    padding: 2em;
    text-align: center;
}