Security check
    flowchart TD
    A[myClass1] --> B[default] & C[default]
    B[default] & C[default] --> D[myClass2]
    classDef default stroke-width:2px,fill:none,stroke:silver
    classDef node color:red
    classDef myClass1 color:#0000ff
    classDef myClass2 stroke:#0000ff,fill:#ccccff
    class A myClass1
    class D myClass2