simple-flexbox-layout.html

<!DOCTYPE html>
<html>
<head>
  <meta charset="utf-8" />
  <title>Holy Grail Layout</title>
  <meta name="viewport" content="width=device-width, initial-scale=1">
  <link rel="stylesheet" type="text/css" media="screen" href="style.css" />
</head>
<body>
  <header>
    <a href="">Nav Left</a>
    <a href="">Nav Right</a>
  </header>
  <main>
    <article>MAIN CONTENT</article>
    <nav>SIDE NAV</nav>
    <aside>ASIDE</aside>
  </main>
  <footer>FOOTER</footer>
</body>
</html>