diff --git a/NEWS.md b/NEWS.md
index c8bb1c7b..852eefe6 100644
--- a/NEWS.md
+++ b/NEWS.md
@@ -1,6 +1,7 @@
 Red Panda C++ Version 3.2
 
   - Change: The way to calcuate astyle path.
+  - fix: Scroll bar arrow size not correct in the dark themes.
 
 Red Panda C++ Version 3.1
 
diff --git a/RedPandaIDE/widgets/darkfusionstyle.cpp b/RedPandaIDE/widgets/darkfusionstyle.cpp
index 73490401..cd83401f 100644
--- a/RedPandaIDE/widgets/darkfusionstyle.cpp
+++ b/RedPandaIDE/widgets/darkfusionstyle.cpp
@@ -98,7 +98,7 @@ static qreal calcDpi() {
 }
 
 static qreal calcDpiScaled(qreal value, qreal dpi) {
-    return value*96/dpi;
+    return value*dpi/96;
 }
 
 }