Minor fix of CSS warning

Author: brunomnsilva

releases/JavaFXSmartGraph-0.9.jar

@@ -418,7 +418,7 @@ private void addVertex(SmartGraphVertexNode<V> v) {
         if (graphProperties.getUseVertexLabel()) {
             SmartLabel label = new SmartLabel(labelText);
 
-            label.setStyle("vertex-label");
+            label.getStyleClass().add("vertex-label");
             this.getChildren().add(label);
             v.attachLabel(label);
         }
@@ -441,7 +441,7 @@ private void addEdge(SmartGraphEdgeBase e, Edge<E, V> edge) {
         if (graphProperties.getUseEdgeLabel()) {
             SmartLabel label = new SmartLabel(labelText);
 
-            label.setStyle("edge-label");
+            label.getStyleClass().add("edge-label");
             this.getChildren().add(label);
             e.attachLabel(label);
         }