Border box around marker with Leaflet & OpenStreetMap

I customized the marker in Leaflet in order to change it’s color. I am using an SVG image for the marker. Unfortunately there is a border box around the marker. I would like to remove the border box. I am not sure what is causing the boarder box. Is it something I need to modify the SVG itself? Or a setting in Leaflet?

I am using the latest version of Mozilla Firefox to view the map.

Marker