Worked on the DefiLlama/defillama-app repository, focusing on enhancing the robustness and reliability of the front end. Addressed a critical issue by implementing boundary checks in the theme cookie parsing logic, ensuring that malformed cookies no longer cause errors during session handling. This change improved the consistency and security of theme behavior by validating cookie values before parsing, directly impacting user experience stability. Utilized TypeScript and front end development skills to deliver this targeted bug fix. No new product-facing features were introduced during this period, as the primary emphasis was on strengthening the application's core user experience and security posture.