This example demonstrates asynchronous programming patterns using JavaScript Promises, with text updates appearing sequentially in two HTML divs. It shows how a chain of `Promise` objects, created through the `setTimeout` function, executes one after another, updating the visual output after each one-second delay. The visualization uses D3.js v5 through the `select` function to modify text content, while a separate module file exports an unused string constant. The styling relies on the Ubuntu font from Google Fonts with a dark background and light text, though the core interaction is purely timing-based rather than data-driven.