1%%{init: {'theme': 'base', 'themeVariables': {'actorBkg': '#e3f2fd', 'actorBorder': '#1976d2', 'signalColor': '#333', 'noteBkgColor': '#fff9c4', 'noteBorderColor': '#f9a825'}}}%%
2sequenceDiagram
3    participant Client
4    participant API
5    Client->>API: POST /upload
6    API-->>Client: 200 OK