diff --git a/webapp/IronCalc/src/components/BorderPicker/BorderPicker.tsx b/webapp/IronCalc/src/components/BorderPicker/BorderPicker.tsx
index e02574c..2ca57b4 100644
--- a/webapp/IronCalc/src/components/BorderPicker/BorderPicker.tsx
+++ b/webapp/IronCalc/src/components/BorderPicker/BorderPicker.tsx
@@ -361,7 +361,7 @@ const MediumLine = styled("div")`
 `;
 const ThickLine = styled("div")`
   width: 68px;
-  border-top: 1px solid ${theme.palette.grey["900"]};
+  border-top: 3px solid ${theme.palette.grey["900"]};
 `;
 
 const Divider = styled("div")`