Proficiency in HTML5, CSS3, and JavaScript, with experience in modern front-end frameworks/libraries (e.g., React, Angular, Vue.js).Familiarity with mobile development frameworks/libraries (e.g., React Native, Flutter) and mobile platform-specific considerations.Experience with responsive design principles and frameworks (e.g., Bootstrap, Material Design).Knowledge of cross-browser compatibility issues and strategies to address them.Strong understanding of mobile-first and progressive enhancement approaches.Experience with version control systems, especially Git.Experience with server-side programming languages and frameworks (e.g., Node.js, Express.js) for full-stack development.Understanding of web security principles and best practices.Familiarity with RESTful APIs and asynchronous request handling.