diff --git a/Eino/quick_start/chapter_02_chatmodelagent_runner_agentevent.md b/Eino/quick_start/chapter_02_chatmodelagent_runner_agentevent.md
index 1e845a6..5cce980 100644
--- a/Eino/quick_start/chapter_02_chatmodelagent_runner_agentevent.md
+++ b/Eino/quick_start/chapter_02_chatmodelagent_runner_agentevent.md
@@ -114,6 +114,7 @@ type Agent interface {
 
 ```mermaid
 flowchart LR
+    classDef noteStyle fill:#fff3e0,stroke:#ffb74d,stroke-width:2px
     A["Agent 接口"] --> B["ChatModelAgent"]
     A --> C["WorkflowAgent"]
     A --> D["SupervisorAgent"]
@@ -121,9 +122,8 @@ flowchart LR
     B --> F["统一 Runner 执行"]
     C --> F
     D --> F
-    G["统一抽象<br/>运行时多态"] :::noteStyle
-    F -.-> G
-    classDef noteStyle fill:#fff3e0,stroke:#ffb74d,stroke-width:2px;
+    F -.-> G["统一抽象<br/>运行时多态"]
+    class G noteStyle
 ```
 
 1. **统一抽象**：所有 Agent 类型都实现同一个接口，Runner 无需关心 Agent 内部实现