CSS @container scroll-state: Replace JS scroll listeners now

Scroll containers have traditionally been a challenge in CSS, often requiring JavaScript to manage scroll-driven effects like sticky navigation bars or photo reactions. This approach, reliant on scroll listeners and manual measurements, often resulted in performance issues and UI lag. However, the introduction of the @container scroll-state feature in CSS offers a more efficient, declarative solution by allowing CSS to directly respond to an element’s position within its scroll container. This change reduces the need for JavaScript, as the browser’s rendering engine now handles state detection internally, leading to smoother interfaces and less code complexity. By defining scroll-state containers and using the @container at-rule with conditions such as stuck, snapped, or scrollable, developers can achieve dynamic styling without performance drawbacks. This new feature, available in Chrome 133 and later, represents a significant shift in building scroll-driven interfaces, emphasizing progressive enhancement and simplifying code while improving user experience.