diff --git a/docs/protocol.md b/docs/protocol.md
index f46aa80..42f94d8 100644
--- a/docs/protocol.md
+++ b/docs/protocol.md
@@ -29,10 +29,11 @@ flowchart TD
 Every message on the wire is a frame:
 
 ```mermaid
+%%{init: {'packet': {'bitsPerRow': 16}}}%%
 packet-beta
 0-15: "message_type"
 16-47: "payload_length"
-48-79: "payload …"
+48-63: "payload …"
 ```
 
 Total header size: **6 bytes**. `payload_length` is the byte count of the payload only — it does not include the 6-byte header itself.