diff --git a/module/assets/leaflet/leaflet/leaflet.css b/module/assets/leaflet/leaflet/leaflet.css
index 1232550..3b944df 100644
--- a/module/assets/leaflet/leaflet/leaflet.css
+++ b/module/assets/leaflet/leaflet/leaflet.css
@@ -278,12 +278,12 @@
 	border-radius: 5px;
 	}
 .leaflet-control-layers-toggle {
-	background-image: url(images/layers.png);
+	background-image: url('images/layers.png');
 	width: 36px;
 	height: 36px;
 	}
 .leaflet-retina .leaflet-control-layers-toggle {
-	background-image: url(images/layers-2x.png);
+	background-image: url('images/layers-2x.png');
 	background-size: 26px 26px;
 	}
 .leaflet-touch .leaflet-control-layers-toggle {