graph TD
    subgraph User["User Application"]
        API["C++ API · Python Bindings · CLI"]
    end

    subgraph Frontend["Circuit Frontend"]
        QASM["QASM / Qiskit"]
        IR["Circuit IR"]
        PE["Prediction Engine"]
    end

    subgraph Backends["Simulation Backends"]
        CPU["CPU<br/>SV · MPS · Stabilizer<br/>TN · Pauli Prop"]
        GPU["GPU<br/>SV · MPS · TN<br/>Pauli Prop"]
        QUEST["QuEST<br/>SV · MPI"]
        COMP["Composite<br/>p-block"]
    end

    subgraph Infra["Infrastructure"]
        SCHED["Scheduler"]
        NET["Network<br/>(DQC)"]
        EST["Estimators"]
    end

    API --> QASM
    QASM --> IR
    IR --> PE
    PE --> CPU
    PE --> GPU
    PE --> QUEST
    PE --> COMP
    IR --> SCHED
    SCHED --> NET
    IR --> EST

    style User fill:#1a1a2e,stroke:#7c3aed,color:#e0e0e0
    style Frontend fill:#16213e,stroke:#7c3aed,color:#e0e0e0
    style Backends fill:#0f3460,stroke:#7c3aed,color:#e0e0e0
    style Infra fill:#1a1a2e,stroke:#7c3aed,color:#e0e0e0
    style GPU fill:#533483,stroke:#e94560,color:#fff
    style QUEST fill:#1e5631,stroke:#4ecca3,color:#fff
