Key Heatmap Features
Dynamic Treemap Simulation: While true Treemaps require complex SVG algorithms, this tool uses a CSS Grid Span logic. Larger companies (by Market Cap) span two columns, creating a visual hierarchy similar to professional terminals like Finviz.
Color-Intensity Mapping: The
getColor()function uses RGBA alpha channels to dim or brighten the tile. A +0.1% gain will be a faint green, while a +4% gain will be a solid, vibrant green.Real-Time Data Flow: The
setIntervalfunction mimics a live WebSocket feed, causing the "heat" of the market to pulse as prices update every two seconds.Responsive Portfolio Integration: The sidebar provides a traditional list view and total P/L calculation, ensuring that while the heatmap gives you the "big picture," the data numbers are still precisely accessible.
How to read this tool:
Green Squares: Bullish momentum. The brighter the green, the stronger the buying pressure.
Red Squares: Bearish momentum. Deep red indicates a sell-off in that specific sector.
Tile Size: Represents the relative weight of that company in the market. Large tiles moving red can drag the whole index down.