diff --git a/docs/architecture.md b/docs/architecture.md
index 1eb70ff2..f73bfdc2 100644
--- a/docs/architecture.md
+++ b/docs/architecture.md
@@ -120,7 +120,7 @@ flowchart TD
            [Domain]
         
           Send Tx to cluster")
-    subgraph History
+    subgraph History 
         History("History
                    [Domain]