fix color

editor/graphDrawing.ml

@@ -100,9 +100,10 @@ module GraphEditor (G: GRAPH ) = struct
 
   let clean s =
     let ctx = s.ctx in
-    let color = CSS.Color.string_of_t (CSS.Color.rgb 220 220 220) in
+    (*let color = CSS.Color.string_of_t (CSS.Color.rgb 220 220 220) in
     ctx##.fillStyle := (Js.string  color);
-    ctx##(fillRect 0.0 0.0 (float width) (float height));
+    ctx##(fillRect 0.0 0.0 (float width) (float height));*)
+    ctx##(clearRect 0.0 0.0 (float width) (float height));
     let colors = CSS.Color.string_of_t (CSS.Color.rgb 0 0 0) in
     ctx##.strokeStyle := (Js.string colors)