diff --git a/toonz/sources/toonz/pltgizmopopup.cpp b/toonz/sources/toonz/pltgizmopopup.cpp
index 7cd428a..73f531a 100644
--- a/toonz/sources/toonz/pltgizmopopup.cpp
+++ b/toonz/sources/toonz/pltgizmopopup.cpp
@@ -166,7 +166,7 @@ public:
       tmpmatte = 0;
     else if (tmpmatte > 255)
       tmpmatte = 255;
-    color.m    = tmpmatte;
+    color.m = tmpmatte;
     return color;
   }
 };
@@ -186,7 +186,7 @@ public:
       tmpmatte = 0;
     else if (tmpmatte > 255)
       tmpmatte = 255;
-    color.m    = tmpmatte;
+    color.m = tmpmatte;
     return color;
   }
 };
@@ -377,11 +377,11 @@ void modifyColor(const T &modifier) {
   TUndo *undo;
   TStyleSelection *selection = dynamic_cast<TStyleSelection *>(
       TApp::instance()->getCurrentSelection()->getSelection());
-  if (selection) {
+  if (selection && !selection->isEmpty()) {
     undo = new GizmoUndo(*selection);
     getStyleIds(styleIds, *selection);
   }
-  /*-- StyleSelectionが有効でない場合はカレントStyleを用いる --*/
+  // modify the current style if the style selection is not active or is empty
   else {
     TStyleSelection tmpSelection;
     tmpSelection.setPaletteHandle(paletteHandle);