```mermaid
graph TD
  %% Host and Bridges
  subgraph Host_Machine_LXD
    H0[LXD Host]
    H0 --> B1[br-lan: IPv4/IPv6 LAN]
    H0 --> B2[br-wan: Simulated WAN]
  end

  %% LAN Zone
  subgraph LAN_Zone
    B1 --> R1[Router: VyOS or Ubuntu with radvd/DHCPv6/NAT64]
    R1 --> C1[Client1: IPv6-only]
    R1 --> C2[Client2: Dual-Stack]
    R1 --> C3[Client3: IPv4-only]
    R1 --> S1[WebServer: Dual-Stack NGINX + DNS]
  end

  %% WAN Zone
  subgraph WAN_Zone
    B2 --> ISP[ISP Router (simulated)]
    ISP --> EXT[External IPv6 Service or Tunnel Broker]
  end

  %% Logical Routing
  R1 --> ISP
  C1 --> R1
  C2 --> R1
  C3 --> R1
```