html,
body {
    margin: 0;
    padding: 0;
}

input,
textarea,
button {
    font-size: 18px;
    margin-bottom: 6px;
    box-sizing: border-box;
}

input,
textarea {
    width: 100%;
}

#output {
    width: 100%;
    height: 251px;
    border: solid 1px;
    font-size: 18px;
}