Customizing cell backgrounds in Excel is one of the fastest ways to transform a plain data dump into a professional, scannable report. Whether you need to highlight headers, flag key metrics, or add visual polish to dashboards, the Free Spire.XLS for .NET library makes it easy to apply solid fills , texture patterns , and gradient effects programmatically. In this guide, you'll learn how to implement each style with concise C# examples. Prerequisites Install the libra...