* {
    box-sizing: border-box;
}

html,body {
    font-family: sans-serif;
    line-height: 1.2rem;
}

h1 {
    color: green;
    margin-left: .5rem;
}

input[type="button"] {
    font-size: 5em;
    font-weight: bold;
}

.textarea > label {
  display: block;
}

.box {
  box-shadow: -1px 2px 5px gray;
  padding: .2rem .5rem;
  margin-bottom: 2rem;
  max-width: 800px;
}

.box .row {
  margin: 0.45em 0;
}

.ciphertext {
  font-size:  1.2em;
  margin-bottom: 1em;
}