leaflet.js map with line and options by d3noob

index.html

<!DOCTYPE html>
<html>
<head>
    <title>Simple Leaflet Map</title>
    <meta charset="utf-8" />
    <link 
        rel="stylesheet" 
        href="//cdn.leafletjs.com/leaflet-0.7/leaflet.css"
    />
</head>
<body>
    <div id="map" style="width: 600px; height: 400px"></div>

    <script
        src="//cdn.leafletjs.com/leaflet-0.7/leaflet.js">
    </script>

    <script>
        var map = L.map('map').setView([-41.2858, 174.78682], 14);
        mapLink = 
            '<a href="//openstreetmap.org">OpenStreetMap</a>';
        L.tileLayer(
            '//{s}.tile.openstreetmap.org/{z}/{x}/{y}.png', {
            attribution: '&copy; ' + mapLink + ' Contributors',
            maxZoom: 18,
            }).addTo(map);
        
        var polyline = L.polyline([
            [-41.286, 174.796],
            [-41.281, 174.786],
            [-41.279, 174.776],
            [-41.290, 174.775],
            [-41.292, 174.788]
            ],
            {
                color: 'red',
                weight: 10,
                opacity: .7,
                dashArray: '20,15',
                lineJoin: 'round'
            }
            ).addTo(map);
        
    </script>
</body>
</html>