A stacked bar chart displays the distribution of religious affiliations across countries, using a dataset of the top 20 countries by religious population. The visualization is built with the Vega-Lite API, which constructs a specification rendered by Vega, and incorporates D3 for data loading. The chart encodes country on the x-axis, population on the y-axis, and religion as color, with tooltips showing religion details. The design is customized via a config object for axis and label styling, and the visualization fills the browser window.