The issue requests a mobile table of contents similar to the desktop catalog. Start by examining how the desktop catalog is generated (likely from heading tags) and how the navigation icon works on mobile. Look at files in ` includes`, ` layouts`, `assets/css`, and `assets/js` to understand the current structure. Check if there is a Jekyll plugin for table of contents. Review comments for any suggested approaches. Implement a collapsible or scrollable catalog that appears on mobile when tapping an icon.
