Leaflet layer panel

Question

The layer icon is blank in my leaflet map. In other words, the small gray rectangles inside the box are not visible. How can I make it visible?

And my code for overlays:

  var Commune = new L.LayerGroup();

  var CommuneStVeran = [
  [ 44.654816299146773, 6.948335091404863,], 
  [ 44.652132288291128, 6.939938792686195,],
  [ 44.659796388551648, 6.915266605877861,];

  var polygon = L.polygon(CommuneStVeran, { color: '#666633',
  weight: 5,
  opacity: 0.65,
  fillColor: "ff7800",
  fillOpacity: 0.23}).addTo(Commune);

   var overlays = {
    "Limites de la commune":Commune
   }; 


    var Centroïde = L.icon({
    iconUrl: 'icon-gamze/centroid.png',
    iconSize: [40,40], // size of the icon,

    });



   overlays ['Centroïde de la commune (lang, lat)'] = L.marker([44.68452505169315, 6.890594241034665], {icon: Centroïde}).bindPopup("<b>Longitude, Latitude</b><br>44.68452, 6.89059").openPopup().addTo(map);

Answer 1

Not only css and js files, but also "images" files should be included in the css folder while working in a local setting. All can be downloaded from http://leafletjs.com/download.html

Answer 2

Here I made a JSFIDDLE for you with some code. Hope that should help you.