<Excel Red and Black Expanded> 
1. Primary Red - 
                            
                            #FF0000
                         - A bold and vibrant red that embodies energy and passion, perfect for highlighting key elements in Excel.
2. Deep Black - 
                            
                            #000000
                         - A classic black that provides a strong contrast, ideal for text and data outlines.
3. Soft Gray - 
                            
                            #D3D3D3
                         - A light gray that can be used as a neutral background, allowing red and black to stand out.
4. Dark Gray - 
                            
                            #A9A9A9
                         - A darker gray for subtle distinctions, useful for secondary elements or inactive states.
5. Accent Red - 
                            
                            #C72C2C
                         - A slightly muted red that can serve as an accent color for charts and graphs without overwhelming the viewer.
6. Bright White - 
                            
                            #FFFFFF
                         - A clean white that enhances readability and can be used for backgrounds or text to maximize contrast.
7. Charcoal Gray - 
                            
                            #333333
                         - A deep charcoal that adds sophistication and can be used for headers or footers.
8. Light Red - 
                            
                            #FF6666
                         - A softer red that can be utilized for highlighting data without being too aggressive.
9. Silver - 
                            
                            #C0C0C0
                         - A metallic silver that brings a touch of elegance, suitable for borders or emphasis in visual elements.
10. Burgundy - 
                            
                            #800000
                         - A rich, dark red that conveys depth and can be used for secondary emphasis in charts or tables.

This expanded color palette maintains the core theme of red and black while introducing additional shades that enhance versatility and visual interest.

Would you like to explore how to implement these colors in specific Excel features, such as conditional formatting or a template design?