map.html

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>My NSBM Map</title>
    <link rel="stylesheet" href="https://unpkg.com/leaflet/dist/leaflet.css" />
    <link rel="stylesheet" href="https://cdn.jsdelivr.net/npm/bootstrap@4.4.1/dist/css/bootstrap.min.css"
     integrity="sha384-Vkoo8x4CGsO3+Hhxv8T/Q5PaXtkKtu6ug5TOeNV6gBiFeWPGFN9MuhOf23Q9Ifjh" crossorigin="anonymous">
    <style>
        #map {
            height: 500px;
        }
    </style>
</head>
<body>
    <div id="map"></div>
    <div id="markers" style="display: none;"></div>

    <script src="https://unpkg.com/leaflet/dist/leaflet.js"></script>
    <script src="script.js"></script>
</body>
</html>