Web App Completion & UI Refinement

I am looking for a developer to complete the remaining ~20% of a web application with a clean, modern interface.The application is already ~80% built. I need help with: - Final UI/UX refinements - Fixing... (Budget: $250 - $750 USD, Jobs: Frontend Development, HTML5, JavaScript, React.js, UI / User Interface, User Interface / IA, Web Development, Website Design)