RSS Feed Widget is a lightweight, zero-dependency JavaScript library that turns any RSS feed into a responsive card grid. It works with a single script tag and three lines of code, with no frameworks or build tools required. Features include automatic image display from RSS enclosure tags, dark mode that detects system preferences, category filtering, skeleton loading animations, and WCAG AA accessibility compliance. The library is under 7KB gzipped, supports XSS sanitization for safe embedding of external feeds, and is available on npm and GitHub under the MIT license.