<!DOCTYPE html>
<html lang="en-US">
  <head>
    <meta charset="utf-8">
    <meta name="viewport" content="width=device-width">
    <title>:required and :optional with generated content</title>
    <link href="https://fonts.googleapis.com/css?family=Josefin+Sans&display=swap" rel="stylesheet">
    <style>
      body {
        font-family: 'Josefin Sans', sans-serif;
        margin: 20px auto;
        max-width: 460px;
      }

      fieldset {
        padding: 10px 30px 0;
      }

      legend {
        co