graph LR
    R[Request] -->|www|C[Firewall/Loadbalancer]
    C-->RP
      RP-->F
      RP-->B
      B-->|API|DB
    
    subgraph subID[replicable VPS]
      RP{Nginx: Reverse Proxy :80 }
      F(Nginx: Frontend React : 81)
      B(NodeJS: Backend : 4001)
    end
    subgraph MongoDB<br/>Atlas Service*
      DB[(MongoDB)]
    end
    style subID color:white,fill:#f9ff9,stroke:yellow
    style B color:black,fill:#f91,stroke:#313,stroke-width:4px
    style F color:white,fill:#191,stroke:#313,stroke-width:4px