td {
    width: 20px;
    text-align: center;
}

table {
    margin: 0 auto;
}

#plaintext, #ciphertext {
    width: 95%;
    max-width: 95%;
    height: 50px;
}

#encodeButton, #decodeButton {
    width: 20px;
    margin: auto;
}

.wrapper {
    margin: auto 20px;
    width: 81px;
}