diff --git a/dgl/StandaloneWindow.hpp b/dgl/StandaloneWindow.hpp
index 9ba0beeb..3d54e27e 100644
--- a/dgl/StandaloneWindow.hpp
+++ b/dgl/StandaloneWindow.hpp
@@ -68,7 +68,7 @@ public:
     }
 
 protected:
-    App fApp;
+    App    fApp;
     Window fWindow;
 };
 
diff --git a/dgl/src/Window.cpp b/dgl/src/Window.cpp
index f0517dfe..b7632181 100644
--- a/dgl/src/Window.cpp
+++ b/dgl/src/Window.cpp
@@ -476,7 +476,7 @@ public:
     void setTransientWinId(const intptr_t winId)
     {
 #if defined(DGL_OS_LINUX)
-        XSetTransientForHint(xDisplay, xWindow, static_cast<::Window>(winId));
+        XSetTransientForHint(xDisplay, xWindow, static_cast< ::Window>(winId));
 #else
         return;
         // unused