The Mermaid diagram cannot be displayed properly

[rechardwang]

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Dify version

1.3.0

Cloud or Self Hosted

Self Hosted (Docker)

Steps to reproduce

If I use a slightly more complex code, it will throw an error, but this code can be fully displayed in https://mermaid.live/, please help me see what the problem is

```mermaid
graph TD
    classDef structure fill:#e6f7ff,stroke:#3399ff
    classDef mechanism fill:#e6ffe6,stroke:#33cc33
    classDef effect fill:#fff5e6,stroke:#ff9933
    classDef application fill:#f9e6ff,stroke:#cc33ff
    subgraph "聚二甲基硅氧烷（PDMS）结构特性"
        A["化学结构：重复-O-Si(CH3)2-单元"]:::structure
        B["分子量：100-10000 Da"]:::structure
        C["性质：疏水/低表面张力"]:::structure
    end
    subgraph "作用层级与靶点"
        D["皮肤屏障系统"]:::mechanism
        E["毛发表面"]:::mechanism
        A -->|"高分子量<br>线性结构"| D
        A -->|"低粘度特性"| E
    end
    subgraph "分子作用机制"
        F["物理屏障形成"]:::mechanism
        G["摩擦系数降低"]:::mechanism
        D --> F
        E --> G
        F -->|"膜层氧渗透率>10000 Barrer"| H["透氧不透水"]:::effect
        G -->|"摩擦系数<0.1"| I["顺滑触感"]:::effect
    end
    subgraph "生物学效应"
        H --> J["减少TEWL（经皮水分流失）"]:::effect
        J -->|"24小时角质层含水量+30%"| K["长效保湿"]:::effect
        I --> L["梳理阻力降低50%"]:::effect
    end
    subgraph "应用场景"
        M["护肤：防晒/保湿霜膜架构"]:::application
        N["护发：洗发水顺滑剂"]:::application
        K --> M
        L --> N
    end
    style A stroke-width:2px
    style D stroke-dasharray:5 5
    linkStyle 0 stroke:#3399ff,stroke-width:2px
    linkStyle 3 stroke:#33cc33,stroke-width:1.5px

An error is displayed in dify

<img width="591" alt="Image" src="https://github.com/user-attachments/assets/bd32f2bb-b7e7-4630-a254-6e217d776fc0" />


### ✔️ Expected Behavior

_No response_

### ❌ Actual Behavior

_No response_

[hacksider]

nope