diff --git a/config/locales/en.yml b/config/locales/en.yml
index 81979583af5f..302f58edbfbd 100644
--- a/config/locales/en.yml
+++ b/config/locales/en.yml
@@ -48,16 +48,9 @@ en:
         accent-color: "Accent"
         header-bg-color: "Header background"
         header-item-bg-hover-color: "Header background on hover"
-        header-item-font-color: "Header font"
-        header-item-font-hover-color: "Header font on hover"
-        header-border-bottom-color: "Header border"
         main-menu-bg-color: "Main menu background"
         main-menu-bg-selected-background: "Main menu when selected"
         main-menu-bg-hover-background: "Main menu on hover"
-        main-menu-font-color: "Main menu font"
-        main-menu-selected-font-color: "Main menu font when selected"
-        main-menu-hover-font-color: "Main menu font on hover"
-        main-menu-border-color: "Main menu border"
       custom_colors: "Custom colors"
       customize: "Customize your OpenProject installation with your own logo and colors."
       enterprise_notice: "As a special 'Thank you!' for their financial contribution to develop OpenProject, this tiny add-on is only available for Enterprise edition support subscribers."
diff --git a/db/migrate/20241015081341_remove_obsolete_design_variables.rb b/db/migrate/20241015081341_remove_obsolete_design_variables.rb
new file mode 100644
index 000000000000..641b7c1af75f
--- /dev/null
+++ b/db/migrate/20241015081341_remove_obsolete_design_variables.rb
@@ -0,0 +1,21 @@
+class RemoveObsoleteDesignVariables < ActiveRecord::Migration[7.1]
+  OBSOLETE_COLOR_VARIABLES = %w( main-menu-font-color
+                                 main-menu-selected-font-color
+                                 main-menu-hover-font-color
+                                 main-menu-border-color
+                                 header-item-font-color
+                                 header-item-font-hover-color
+                                 header-border-bottom-color ).freeze
+
+  class MigrationDesignColor < ApplicationRecord
+    self.table_name = "design_colors"
+  end
+
+  def up
+    MigrationDesignColor.where(variable: OBSOLETE_COLOR_VARIABLES).delete_all
+  end
+
+  def down
+    # This is not revertible
+  end
+end
diff --git a/lib/open_project/custom_styles/color_themes.rb b/lib/open_project/custom_styles/color_themes.rb
index d5624ee35eb4..b550e312de35 100644
--- a/lib/open_project/custom_styles/color_themes.rb
+++ b/lib/open_project/custom_styles/color_themes.rb
@@ -48,16 +48,9 @@ module ColorThemes
           "accent-color" => ACCENT_COLOR,
           "header-bg-color" => "#1A67A3",
           "header-item-bg-hover-color" => "#175A8E",
-          "header-item-font-color" => "#FFFFFF",
-          "header-item-font-hover-color" => "#FFFFFF",
-          "header-border-bottom-color" => "",
           "main-menu-bg-color" => "#333739",
           "main-menu-bg-selected-background" => "#175A8E",
           "main-menu-bg-hover-background" => "#124E7C",
-          "main-menu-font-color" => "#FFFFFF",
-          "main-menu-hover-font-color" => "#FFFFFF",
-          "main-menu-selected-font-color" => "#FFFFFF",
-          "main-menu-border-color" => "#EAEAEA"
         }
       },
       {
@@ -67,16 +60,9 @@ module ColorThemes
           "accent-color" => ACCENT_COLOR,
           "header-bg-color" => "#FAFAFA",
           "header-item-bg-hover-color" => "#E1E1E1",
-          "header-item-font-color" => "#313131",
-          "header-item-font-hover-color" => "#313131",
-          "header-border-bottom-color" => "#E1E1E1",
           "main-menu-bg-color" => "#ECECEC",
           "main-menu-bg-selected-background" => "#A9A9A9",
           "main-menu-bg-hover-background" => "#FFFFFF",
-          "main-menu-font-color" => "#000000",
-          "main-menu-hover-font-color" => "#000000",
-          "main-menu-selected-font-color" => "#000000",
-          "main-menu-border-color" => "#EAEAEA"
         },
         logo: "logo_openproject.png"
       },
@@ -87,16 +73,9 @@ module ColorThemes
           "accent-color" => ACCENT_COLOR,
           "header-bg-color" => "#05002C",
           "header-item-bg-hover-color" => "#163473",
-          "header-item-font-color" => "#FFFFFF",
-          "header-item-font-hover-color" => "#FFFFFF",
-          "header-border-bottom-color" => "",
           "main-menu-bg-color" => "#0E2045",
           "main-menu-bg-selected-background" => "#3270DB",
           "main-menu-bg-hover-background" => "#163473",
-          "main-menu-font-color" => "#FFFFFF",
-          "main-menu-hover-font-color" => "#FFFFFF",
-          "main-menu-selected-font-color" => "#FFFFFF",
-          "main-menu-border-color" => "#EAEAEA"
         }
       }
     ].freeze