<!doctype html>

<html lang="en">
  <head>
    <meta charset="utf-8" />
    <meta name="viewport" content="width=device-width" />
    <!-- this is an example from the MDN Layout Cookbook -->
    <title>CSS Cookbook: Split Navigation</title>

    <style>
      body {
        background-color: #fff;
        color: #333;
        font:
          1.2em / 1.5 Helvetica Neue,
          Helvetica,
          Arial,
          sans-serif;
        padding: 0;
        margin: 0;
      }

      .main-nav {
        displa