Developer Builds Vanilla JS Quiz App on Day 99 of 100-Day MERN Stack Challenge

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A developer has reached Day 99 of a self-imposed 100-day full-stack engineering challenge focused on MERN stack fundamentals. To mark the penultimate day, they built a dynamic quiz application using only raw HTML, CSS, and Vanilla JavaScript, without any frameworks. The app features array-based question management, index-driven rendering, and real-time visual feedback that highlights correct answers in green and incorrect ones in red. DOM updates are applied to targeted elements rather than the full page, keeping the application lightweight and responsive. The developer plans to launch a complete 100-Days of Code portfolio showcase on Day 100, with all progress tracked in a public GitHub repository.

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