graph LR; A(Client) <==> B[WEB Protal Service] B <==> C[Registry Service]; B --> D[Log Service]; B --> E[Grading Service]; C <==> D; C <==> E; E --> D; style A fill:#f9f,stroke:#333,stroke-width:4px,font-size:32px,color:#000,font-weight:bold,left:100px,top:100px; style B fill:#bbf,stroke:#333,stroke-width:4px,font-size:24px,color:#000,font-weight:bold,left:300px,top:100px; style C fill:#bfb,stroke:#333,stroke-width:4px,font-size:16px,color:#000,font-weight:bold,left:500px,top:100px; style D fill:#fbf,stroke:#333,stroke-width:4px,font-size:100px,color:#000,font-weight:bold,left:700px,top:300px style E fill:#bff,stroke:#333,stroke-width:4px,font-size:12px,color:#000,font-weight:bold,left:700px,top:300px