index.html

<!DOCTYPE html>
<html lang="pt-br">

<head>
  <meta charset="UTF-8">
  <meta http-equiv="X-UA-Compatible" content="IE=edge">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <meta name="description" content="Boilerplate front-end com GULP, SASS e NPM.">
  <title>Boilerplate front-end</title>
  <link rel="prefetch" href="index.html" as="document">
  <link rel="preload" href="build/css/main.css" as="style">
  <link rel="stylesheet" href="build/css/main.css">
  <!-- Javascript -->
  <script defer src="build/js/script.js"></script>
</head>

<body>
  <header class="container">
    <h1 class="heading-primary">Logo</h1>
  </header>

  <main>
    <section class="container">
      <h2 class="heading-secondary">Título 2</h2>
      <h3 class="heading-tertiary">Titulo 3</h3>
    </section>
  </main>

</body>

</html>