demo.html

<div id="map" style="height: 300px; width: 300px"></div>

<script src="https://cdn.jsdelivr.net/npm/leaflet@1.7.1/dist/leaflet.js"></script>
<script src="./dist/leaflet.icon-material.js"></script>
<link href="https://fonts.googleapis.com/icon?family=Material+Icons" rel="stylesheet">
<link rel="stylesheet" href="./dist/leaflet.icon-material.css"></link>
<link rel="stylesheet" href="https://cdn.jsdelivr.net/npm/leaflet@1.7.1/dist/leaflet.css"></link>

<script>

var center = [41.7625, -72.674167]

var map = L.map('map', {
  center: center,
  zoom: 16
})

var CartoDB_DarkMatter = L.tileLayer('https://{s}.basemaps.cartocdn.com/dark_all/{z}/{x}/{y}{r}.png', {
	attribution: '&copy; <a href="https://www.openstreetmap.org/copyright">OpenStreetMap</a> contributors &copy; <a href="https://carto.com/attributions">CARTO</a>',
	subdomains: 'abcd',
	maxZoom: 19
}).addTo(map)

L.marker(center, {
  icon: L.IconMaterial.icon({
    iconColor: 'black'
  })
}).addTo(map)

</script>