diff --git a/config.py b/config.py
index 90744a329..4102679da 100644
--- a/config.py
+++ b/config.py
@@ -58,31 +58,21 @@
 
 CATALOG = 'lang'
 
-isDark = False
-try:
-    isDark = wx.SystemAppearance().IsDark()
-except (KeyboardInterrupt, SystemExit):
-    raise
-except:
-    pass
-
-
-if isDark:
-    slotColourMap = {
-        FittingSlot.LOW: wx.Colour(44, 36, 19),  # yellow = low slots 24/13
-        FittingSlot.MED: wx.Colour(28, 39, 51),  # blue   = mid slots 8.1/9.5
-        FittingSlot.HIGH: wx.Colour(53, 31, 34),  # red    = high slots 6.5/11.5
-        FittingSlot.RIG: '',
-        FittingSlot.SUBSYSTEM: ''}
-    errColor = wx.Colour(70, 20, 20)
-else:
-    slotColourMap = {
-        FittingSlot.LOW: wx.Colour(250, 235, 204),  # yellow = low slots
-        FittingSlot.MED: wx.Colour(188, 215, 241),  # blue   = mid slots
-        FittingSlot.HIGH: wx.Colour(235, 204, 209),  # red    = high slots
-        FittingSlot.RIG: '',
-        FittingSlot.SUBSYSTEM: ''}
-    errColor = wx.Colour(204, 51, 51)
+
+slotColourMapDark = {
+    FittingSlot.LOW: wx.Colour(44, 36, 19),  # yellow = low slots 24/13
+    FittingSlot.MED: wx.Colour(28, 39, 51),  # blue   = mid slots 8.1/9.5
+    FittingSlot.HIGH: wx.Colour(53, 31, 34),  # red    = high slots 6.5/11.5
+    FittingSlot.RIG: '',
+    FittingSlot.SUBSYSTEM: ''}
+errColorDark = wx.Colour(70, 20, 20)
+slotColourMap = {
+    FittingSlot.LOW: wx.Colour(250, 235, 204),  # yellow = low slots
+    FittingSlot.MED: wx.Colour(188, 215, 241),  # blue   = mid slots
+    FittingSlot.HIGH: wx.Colour(235, 204, 209),  # red    = high slots
+    FittingSlot.RIG: '',
+    FittingSlot.SUBSYSTEM: ''}
+errColor = wx.Colour(204, 51, 51)
 
 
 def getClientSecret():
diff --git a/gui/builtinItemStatsViews/helpers.py b/gui/builtinItemStatsViews/helpers.py
index 5a863365a..e6069c526 100644
--- a/gui/builtinItemStatsViews/helpers.py
+++ b/gui/builtinItemStatsViews/helpers.py
@@ -4,13 +4,15 @@
 # noinspection PyPackageRequirements
 import wx.lib.mixins.listctrl as listmix
 
+from gui.utils.dark import isDark
+
 
 class AutoListCtrl(wx.ListCtrl, listmix.ListCtrlAutoWidthMixin, listmix.ListRowHighlighter):
     def __init__(self, parent, ID, pos=wx.DefaultPosition, size=wx.DefaultSize, style=0):
         wx.ListCtrl.__init__(self, parent, ID, pos, size, style)
         listmix.ListCtrlAutoWidthMixin.__init__(self)
         listmix.ListRowHighlighter.__init__(self)
-        if wx.SystemSettings.GetAppearance().IsDark():
+        if isDark():
             listcol = wx.SystemSettings.GetColour(wx.SYS_COLOUR_LISTBOX)
             highlight = listcol.ChangeLightness(110)
             listmix.ListRowHighlighter.SetHighlightColor(self, highlight)
diff --git a/gui/builtinViews/fittingView.py b/gui/builtinViews/fittingView.py
index 996992908..e9f75e109 100644
--- a/gui/builtinViews/fittingView.py
+++ b/gui/builtinViews/fittingView.py
@@ -39,9 +39,10 @@
 from gui.chrome_tabs import EVT_NOTEBOOK_PAGE_CHANGED
 from gui.contextMenu import ContextMenu
 from gui.utils.staticHelpers import DragDropHelper
+from gui.utils.dark import isDark
 from service.fit import Fit
 from service.market import Market
-from config import slotColourMap, errColor
+from config import slotColourMap, slotColourMapDark, errColor, errColorDark
 from gui.fitCommands.helpers import getSimilarModPositions
 
 pyfalog = Logger(__name__)
@@ -729,7 +730,10 @@ def click(self, event):
             event.Skip()
 
     def slotColour(self, slot):
-        return slotColourMap.get(slot) or self.GetBackgroundColour()
+        if isDark():
+            return slotColourMapDark.get(slot) or self.GetBackgroundColour()
+        else:
+            return slotColourMap.get(slot) or self.GetBackgroundColour()
 
     def refresh(self, stuff):
         """
@@ -774,7 +778,7 @@ def refresh(self, stuff):
 
 
                 if slotMap[mod.slot] or hasRestrictionOverriden:  # Color too many modules as red
-                    self.SetItemBackgroundColour(i, errColor)
+                    self.SetItemBackgroundColour(i, errColorDark if isDark() else errColor)
                 elif sFit.serviceFittingOptions["colorFitBySlot"]:  # Color by slot it enabled
                     self.SetItemBackgroundColour(i, self.slotColour(mod.slot))
 
diff --git a/gui/utils/dark.py b/gui/utils/dark.py
new file mode 100644
index 000000000..ca0ace86e
--- /dev/null
+++ b/gui/utils/dark.py
@@ -0,0 +1,10 @@
+import wx
+
+
+def isDark():
+    try:
+        return wx.SystemSettings.GetAppearance().IsDark()
+    except (KeyboardInterrupt, SystemExit):
+        raise
+    except:
+        return False