This example demonstrates a minimal HTML page styled with CSS, rendering the message “Hello HTML!” as the core visualization. It uses plain JavaScript embedded in the page, with a CSS class controlling the large, centered font size. The code highlights the distinction between raw HTML/CSS/JavaScript and the modular, toolchain-driven workflow typical of D3 v3 with React, serving as a simplified baseline for understanding build tools and module bundling in data-visualization projects. No external libraries or data sources are used beyond the standard web platform.