Developed and delivered a light theme feature for the ovh/shai repository’s terminal user interface, focusing on improving user experience and accessibility. The implementation leveraged Rust and environment variable management, enabling automatic theme detection through the SHAI_TUI_THEME variable and supporting dynamic palette updates. Users can toggle between light and dark modes using keyboard shortcuts or commands, reducing onboarding friction and enhancing usability across different environments. The work established a flexible theming foundation for future extensions, aligning with business goals for consistent and accessible interfaces. The project demonstrated proficiency in TUI development, theming strategies, and environment-driven configuration within a Rust codebase.