.theform {
    font-family: 'Roboto', sans-serif;
    text-align: center;
}

* {
    font-family: 'Roboto', sans-serif;
    text-align: center;
}

.letter {
    text-align: center;
    display: inline-block;
    border: 5px solid black;
    width: 40px;
    height: 40px;
    margin-left: auto;
    margin-right: auto;
}