flowchart TB
    Start[Start Here 🚀] --> Fundamentals[01. Fundamentals<br/>What & Why, OOP Refresher]
    Fundamentals --> SOLID[02. SOLID Principles<br/>S O L I D]
    SOLID --> Creational[03. Creational Patterns<br/>Object Creation]
    Creational --> Structural[04. Structural Patterns<br/>Object Composition]
    Structural --> Behavioral[05. Behavioral Patterns<br/>Object Interaction]
    Behavioral --> Practical[06. Practical Guide<br/>When to Use What]
    Practical --> Interview[07. Interview Prep<br/>Common Q&A]

    style Start fill:#7c3aed,color:#fff
    style Fundamentals fill:#3b82f6,color:#fff
    style SOLID fill:#059669,color:#fff
    style Creational fill:#06b6d4,color:#fff
    style Structural fill:#f59e0b,color:#fff
    style Behavioral fill:#ef4444,color:#fff
    style Practical fill:#8b5cf6,color:#fff
    style Interview fill:#ec4899,color:#fff

flowchart LR
    subgraph Creational["🏗️ Creational"]
        S1[Singleton]:::c
        F1[Factory Method]:::c
        AF[Abstract Factory]:::c
        B1[Builder]:::c
        P1[Prototype]:::c
    end
    subgraph Structural["🔧 Structural"]
        Ad[Adapter]:::s
        Dec[Decorator]:::s
        Fac[Facade]:::s
        Pr[Proxy]:::s
        Com[Composite]:::s
    end
    subgraph Behavioral["🔄 Behavioral"]
        Ob[Observer]:::b
        St[Strategy]:::b
        Cmd[Command]:::b
        It[Iterator]:::b
        Sta[State]:::b
    end
    classDef c fill:#06b6d4,color:#fff
    classDef s fill:#f59e0b,color:#fff
    classDef b fill:#ef4444,color:#fff