pwa-timer/index.html

<!DOCTYPE html>
<html lang="en-US" dir="ltr">
  <head>
    <meta charset="UTF-8" />
    <meta name="viewport" content="width=device-width,initial-scale=1" />
    <link rel="shortcut icon" href="https://c.s-microsoft.com/favicon.ico?v2" />
    <link rel="stylesheet" href="./styles.css">
    <link rel="manifest" href="./manifest.json">
    <title>timer</title>
  </head>
  <body>
    <h1>Timer</h1>
    <form>
      Remind me to
      <input type="text" id="reminder" placeholder="wake up" value="take a break" />
      in
      <input type="number" id="time-qty" placeholder="10" value="5" />
      <select id="time-unit" title="Time unit">
        <option value="seconds" selected>seconds</option>
        <option value="minutes">minutes</option>
        <option value="hours">hours</option>
        <option value="days">days</option>
      </select>
      <button id="set-timer" type="submit">Set timer</button>
    </form>

    <ul class="timers"></ul>

    <script src="./script.js"></script>
    <script>
      if('serviceWorker' in navigator) {
        navigator.serviceWorker.register('./sw.js', { scope: './' });
      }
    </script>
  </body>
</html>