L.Circle
extends L.Path
(http://leafletjs.com/reference.html#path), that have method setStyle( <Path options> object )
, and you can apply new style as window.circle.setStyle({fillColor: '#dddddd'});
L.Circle
extends L.Path
(http://leafletjs.com/reference.html#path), that have method setStyle( <Path options> object )
, and you can apply new style as window.circle.setStyle({fillColor: '#dddddd'});