body {
    border-style: solid;
    border-width: 1px;
    border-color: black;

    position: absolute;
    top:0px;
    right:0px;
    bottom:0px;
    left:0px;

    margin: 0px;
    padding: 0px;

    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
}

h3 {
    margin: 0;
}

span {
    text-align: center;
}