This example demonstrates focus+context area charts using D3.js, with a linked brush that filters a detailed view. The main chart (focus) displays the full dataset as a filled area, while a smaller context chart beneath it shows the same data. When a brush is dragged across the context chart, it defines a time interval that automatically updates the focus chart's x-axis domain, enabling zooming and panning. The implementation uses Chiasm components for reactive data flow, with the brush interval acting as a shared state between the two views. The visualization effectively illustrates how brushing and linking can provide both overview and detail in time-series data exploration.