ElegantFin is a comprehensive CSS theme for the Jellyfin media server, providing a modern, dark UI overhaul inspired by Jellyseerr. It is delivered as a single CSS import and relies entirely on CSS custom properties (design tokens) for customization, allowing users to adjust colors, layout, and visibility toggles. The theme is built with PostCSS and includes optional add-on stylesheets for custom media covers and third-party plugin support. The codebase consists of versioned, monolithic CSS files that override Jellyfin's default styling across desktop, mobile, and TV layouts. It is not an application backend or data pipeline; it is a pure client-side presentation layer. The theme demonstrates strong CSS craftsmanship through extensive use of modern selectors (`:has()`, `@container`, `@supports`), responsive card grids, and design token abstraction, though it suffers from duplication across versions and reliance on external CDN resources.