_layouts/base.html

<!doctype html>
<html>

<head>

  <meta charset="utf-8">
  <meta http-equiv="X-UA-Compatible" content="IE=edge">
  <meta name="viewport" content="width=device-width, initial-scale=1, shrink-to-fit=no">

  <title>{% assign title_is_not_empty = page.title | is_not_empty %}{% if title_is_not_empty %}{{ page.title }} - {% endif %}{{ site.title }}</title>
  <!-- Favicon-->
  <link rel="icon" type="image/x-icon" href="assets/img/favicon.ico" />
  <!-- Font Awesome icons (free version)-->
  <link rel="stylesheet" href="https://use.fontawesome.com/releases/v5.10.0/css/all.css" crossorigin="anonymous">
  <!-- Google fonts-->
  <link href="https://fonts.googleapis.com/css?family=DM+Serif+Display:400,400i|Roboto+Mono&display=swap" rel="stylesheet">

  <!-- Third party plugin CSS-->
  <link href="https://cdnjs.cloudflare.com/ajax/libs/magnific-popup.js/1.1.0/magnific-popup.min.css" rel="stylesheet" />
  <!-- Core theme CSS (includes Bootstrap)-->
  <link href="assets/css/creative.css" rel="stylesheet">
  <!-- Custom CSS -->
  <link href="assets/css/main.css" rel="stylesheet">

  <!-- HTML5 Shim and Respond.js IE8 support of HTML5 elements and media queries -->
  <!-- WARNING: Respond.js doesn't work if you view the page via file:// -->
  <!--[if lt IE 9]>
      <script src="https://oss.maxcdn.com/libs/html5shiv/3.7.0/html5shiv.js"></script>
      <script src="https://oss.maxcdn.com/libs/respond.js/1.4.2/respond.min.js"></script>
  <![endif]-->
{% seo %}
</head>

<body id="page-top" class="{% if page.layout == site.landing_template %}landing {% endif %}">
  {% include nav.html    section=section site=site page=page %}
  {{ content }}
  {% include footer.html section=section site=site page=page %}

  <!-- Bootstrap core JS-->
  <script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.4.1/jquery.min.js"></script>
  <script src="https://stackpath.bootstrapcdn.com/bootstrap/4.4.1/js/bootstrap.bundle.min.js"></script>
  <!-- Third party plugin JS-->
  <script src="https://cdnjs.cloudflare.com/ajax/libs/jquery-easing/1.4.1/jquery.easing.min.js"></script>
  <script src="https://cdnjs.cloudflare.com/ajax/libs/magnific-popup.js/1.1.0/jquery.magnific-popup.min.js"></script>
  <!-- Core theme JS-->

  <script src="assets/js/creative.min.js"></script>
</body>

</html>