diff --git a/site/posts/2023-03-20-theming-ios-apps.md b/site/posts/2023-03-20-theming-ios-apps.md
index 3a08b42..d753d2c 100644
--- a/site/posts/2023-03-20-theming-ios-apps.md
+++ b/site/posts/2023-03-20-theming-ios-apps.md
@@ -30,11 +30,11 @@ With a simple extension on `UITraitCollection`, you can make it look like any ot
 extension UITraitCollection {
     var pureBlackDarkMode: Bool {
         get {
-            (value(forKey: "_clientDefinedTraits") as? [String: Any])?[key] as? Bool ?? true
+            (value(forKey: "_clientDefinedTraits") as? [String: Any])?["tusker_usePureBlackDarkMode"] as? Bool ?? true
         }
         set {
             var dict = value(forKey: "_clientDefinedTraits") as? [String: Any] ?? [:]
-            dict[key] = newValue
+            dict["tusker_usePureBlackDarkMode"] = newValue
             setValue(dict, forKey: "_clientDefinedTraits")
         }
     }