Demonstration and documentation

We'll scan #main-content-area for <h2> and <h3> tags, and insert it into a placeholder div.table-of-contents.

This method also adds anchor tags to your headers.

Level 2 heading

More content in a full-width container.

Level 3 heading

More content in a full-width container.

Level 4 heading

This won't be added to the table of contents.

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