diff --git a/frontend/src/api/systems.ts b/frontend/src/api/systems.ts
index d5d8012..5206f58 100644
--- a/frontend/src/api/systems.ts
+++ b/frontend/src/api/systems.ts
@@ -31,7 +31,7 @@ export async function updateSystem(
   data: Partial<{
     name: string;
     description: string;
-    color: string;
+    color: string | null;
     status: "active" | "archived";
     order_index: number;
   }>,