graph TD
%% Define CSS-like classes for styling nodes
classDef cited fill:#f9f,stroke:#333,stroke-width:2px;
classDef citing fill:#ccf,stroke:#333,stroke-width:2px;
%% Subgraph for the First Month: January
subgraph January
A[Paper A <br> Jan 5]
B[Paper B <br> Jan 12]
C[Paper C <br> Jan 20]
end
%% Subgraph for the Second Month: February
subgraph February
D[Paper D <br> Feb 2]
E[Paper E <br> Feb 18]
end
%% Subgraph for the Third Month: March
subgraph March
F[Paper F <br> Mar 10]
G[Paper G <br> Mar 25]
end
%% Define the citation links between the nodes
A --> B;
B --> C;
C --> D;
A --> E;
D --> F;
E --> G;
A --> G;
%% Apply the styles to the nodes
class A,C,D,E cited;
class B,G citing;