Dot syntax for Franchise organization graph example

digraph G {

    subgraph franchize {
        style=filled;
        color=lightgrey;
        node [style=filled,color="#0080FF"];
        gs [label="Grocery store"]
        gss [label="Sub-store"]
        emp [label="Employee"]      
        gs -> gss
        gs ->Karen [color=White]
        Karen->gs  [label="isEmployed", fontcolor=darkgreen]
        Karen->emp  [label="isEmployee", fontcolor=darkgreen]
        Karen->gss [label="worksFor",  fontcolor=darkgreen]
    }


    start -> gs  


    start [label="Orgnization of Grocery Store",shape=Mdiamond];
}