The source outlines a technical proposal for new CSS pseudo-elements aimed at solving the "Carousel Problem" by allowing developers to build accessible, interactive carousels without relying on complex JavaScript or extraneous markup. The design introduces ::scroll-marker and ::scroll-button() to enable the browser to automatically generate slide indicators and navigation controls, dramatically simplifying authoring and maintenance. This approach integrates natively with core CSS features like Scroll Snap and manages dynamic states, such as enabling/disabling buttons and highlighting the active slide using the :target-currentpseudo-class. Crucially, the system bakes in WAI-ARIA accessibility features by managing focus order and screen reader roles, ensuring consistent user experience. The document further explains the complex internal browser engine coordination required, including how the marker container is generated as a sibling box to the scrolling element. Ultimately, the proposal seeks to create a more performant and consistently accessiblepattern for ubiquitous UI components.