This example demonstrates a basic HTML and CSS page with a large monospace font and a red-highlighted text class. The page embeds a YouTube video via an iframe, using the YouTube embedded player API for playback. Styling is applied directly through a single CSS file, with the body set to a 3em font size and the `.highlighted` class turning text red. The demonstration focuses on static layout and styling rather than interactive data visualization, with no JavaScript or charting libraries involved.