<Soft Winter Themed Colors with Additional Option> 
1. Header Color - Frosted Pine - 
                            
                            #A8C8D1
                         - A tranquil bluish-green that sets a serene tone for headers, ensuring strong contrast for black text.
2. Alternating Row Color 1 - Soft Apricot - 
                            
                            #F5CBA0
                         - A gentle apricot hue that adds warmth and a subtle festive touch to the spreadsheet.
3. Alternating Row Color 2 - Icy Periwinkle - 
                            
                            #D6E3F2
                         - A soft periwinkle blue that complements the apricot, enhancing readability while maintaining a wintery feel.
4. Dropdown Color 1 - Festive Red - 
                            
                            #C72A2A
                         - A classic Christmas red that stands out for important selections.
5. Dropdown Color 2 - Deep Forest Green - 
                            
                            #2F6D26
                         - A rich green that offers a strong contrast for clarity and visibility in dropdown options.
6. Dropdown Color 3 - Soft Gold - 
                            
                            #E8B54D
                         - A warm gold that adds a touch of elegance and festivity to your dropdown menu.
7. Dropdown Color 4 - Winterberry - 
                            
                            #8D4D6B
                         - A muted berry color that adds diversity and warmth, complementing the other dropdown colors. 

In this palette, the additional header color “Frosted Pine” adds a cool yet inviting touch to the soft winter theme. The colors work harmoniously together to enhance readability while maintaining a festive atmosphere.

Would you like any more color variations or adjustments? Or do you have specific design elements you’d like to explore further?