1. Define the base `ThemeData` for the application, including `ColorScheme` and typography.
2. Override specific component themes using `*ThemeData` classes (e.g., `AppBarThemeData`, `CardThemeData`).
3. Style buttons using `ButtonStyle` and `MaterialStateProperty.resolveWith` for state-dependent styling.
4. Implement adaptive UI components using `Platform` and `DeviceType` to adjust behavior based on the target platform.
5. Wrap widgets in `Scrollbar` and `SelectableText` for desktop/web compatibility.
6. Test the application on different platforms to ensure visual consistency and usability.
7. Refactor and optimize the code for maintainability and performance.