Riffle: Searchable Heading Outlines per Nivyan Lakhani

Riffle is an open-source browser extension that generates a searchable, keyboard-navigable outline from the page's heading elements.

Key Features:
- Dynamic Outline Generation: Creates a hierarchical view from visible elements on the current page.
- Instant Search: Quickly filter the outline by typing any part of a heading's text.
- Keyboard-Centric Navigation: Designed for efficient use without requiring mouse interaction.
- Direct Page Navigation: Select an item in the outline to scroll the corresponding heading into view.
- Hierarchical Control: Expand and collapse individual branches or the entire outline structure.
- Customizable Interface: Adjust theme (System, Light, Dark), font size, and apply custom CSS rules.
- Minimal Design: Focuses on functionality with a clean user interface.

The source code for the extension is hosted at: https://github.com/niv-l/riffle