diff -r -u a/wx+/grid.cpp b/wx+/grid.cpp
--- a/wx+/grid.cpp	 2020-12-05 14:38:39.000000000 +0100
+++ b/wx+/grid.cpp	 2020-12-22 06:36:21.000000000 +0100
@@ -36,10 +36,10 @@
 {
 //------------------------------ Grid Parameters --------------------------------
 inline wxColor getColorLabelText(bool enabled) { return wxSystemSettings::GetColour(enabled ? wxSYS_COLOUR_WINDOWTEXT : wxSYS_COLOUR_GRAYTEXT); }
-inline wxColor getColorGridLine() { return { 192, 192, 192 }; } //light grey
+inline wxColor getColorGridLine() { return wxSystemSettings::GetColour(wxSYS_COLOUR_BTNSHADOW); } //light grey
 
 inline wxColor getColorLabelGradientFrom() { return wxSystemSettings::GetColour(wxSYS_COLOUR_WINDOW); }
-inline wxColor getColorLabelGradientTo  () { return { 200, 200, 200 }; } //light grey
+inline wxColor getColorLabelGradientTo  () { return wxSystemSettings::GetColour(wxSYS_COLOUR_BTNFACE); } //light grey
 
 inline wxColor getColorLabelGradientFocusFrom() { return getColorLabelGradientFrom(); }
 inline wxColor getColorLabelGradientFocusTo  () { return GridData::getColorSelectionGradientFrom(); }
@@ -227,7 +227,7 @@
 {
     //left border
     {
-        wxDCPenChanger dummy(dc, wxPen(*wxWHITE, fastFromDIP(1)));
+        wxDCPenChanger dummy(dc, wxPen(wxSystemSettings::GetColour(wxSYS_COLOUR_BTNSHADOW), fastFromDIP(1)));
         dc.DrawLine(rect.GetTopLeft(), rect.GetBottomLeft());
     }
     //bottom, right border
@@ -444,7 +444,7 @@
 
         wxRect rectShrinked = clientRect;
         rectShrinked.Deflate(fastFromDIP(1));
-        dc.SetPen(wxPen(*wxWHITE, fastFromDIP(1)));
+        dc.SetPen(wxPen(wxSystemSettings::GetColour(wxSYS_COLOUR_BTNSHADOW), fastFromDIP(1)));
 
         //dc.DrawLine(clientRect.GetTopLeft(), clientRect.GetTopRight() + wxPoint(1, 0));
         dc.DrawLine(rectShrinked.GetTopLeft(), rectShrinked.GetBottomLeft() + wxPoint(0, 1));
@@ -545,7 +545,7 @@
 
         //border lines
         {
-            wxDCPenChanger dummy(dc, wxPen(*wxWHITE, fastFromDIP(1)));
+            wxDCPenChanger dummy(dc, wxPen(wxSystemSettings::GetColour(wxSYS_COLOUR_BTNSHADOW), fastFromDIP(1)));
             dc.DrawLine(rect.GetTopLeft(), rect.GetTopRight());
         }
         {
diff -r -u a/FreeFileSync/Source/ui/file_grid.cpp b/FreeFileSync/Source/ui/file_grid.cpp
--- a/FreeFileSync/Source/ui/file_grid.cpp	2020-12-05 14:38:39.000000000 +0100
+++ b/FreeFileSync/Source/ui/file_grid.cpp	2020-12-22 06:05:29.000000000 +0100
@@ -46,7 +46,7 @@
 inline wxColor getColorInactiveBack(bool faint) { if (faint) return { 0xf6, 0xf6, 0xf6}; return { 0xe4, 0xe4, 0xe4 }; } //light grey
 inline wxColor getColorInactiveText() { return { 0x40, 0x40, 0x40 }; } //dark grey
 
-inline wxColor getColorGridLine() { return { 192, 192, 192 }; } //light grey
+inline wxColor getColorGridLine() { return wxSystemSettings::GetColour(wxSYS_COLOUR_BTNSHADOW); } //light grey
 
 const int FILE_GRID_GAP_SIZE_DIP = 2;
 const int FILE_GRID_GAP_SIZE_WIDE_DIP = 6;
diff -r -u a/FreeFileSync/Source/ui/triple_splitter.cpp b/FreeFileSync/Source/ui/triple_splitter.cpp
--- a/FreeFileSync/Source/ui/triple_splitter.cpp	2020-12-05 14:38:39.000000000 +0100
+++ b/FreeFileSync/Source/ui/triple_splitter.cpp	2020-12-22 05:37:32.000000000 +0100
@@ -8,6 +8,7 @@
 #include <algorithm>
 #include <zen/stl_tools.h>
 #include <wx+/dc.h>
+#include <wx/settings.h>
 
 using namespace zen;
 using namespace fff;
@@ -24,8 +25,8 @@
 const int CHILD_WINDOW_MIN_SIZE_DIP = 50; //min. size of managed windows
 
 //let's NOT create wxWidgets objects statically:
-inline wxColor getColorSashGradientFrom() { return { 192, 192, 192 }; } //light grey
-inline wxColor getColorSashGradientTo  () { return *wxWHITE; }
+inline wxColor getColorSashGradientFrom() { return wxSystemSettings::GetColour(wxSYS_COLOUR_BTNSHADOW); } //light grey
+inline wxColor getColorSashGradientTo  () { return wxSystemSettings::GetColour(wxSYS_COLOUR_BTNFACE); }
 }