Great! Here’s a color palette designed for 16 different categories, avoiding neon colors and focusing on a more muted and professional aesthetic.

 <Muted Professional Colors>
1. Light Blue - 
                            
                            #A4C8E1
                         - A soft and calming blue that promotes clarity and organization.
2. Soft Green - 
                            
                            #B7E1B5
                         - A gentle green that conveys growth and balance.
3. Light Gray - 
                            
                            #D3D3D3
                         - A neutral tone that adds a sense of professionalism and simplicity.
4. Dusty Rose - 
                            
                            #EAB8C8
                         - A warm and inviting pink that adds a touch of comfort.
5. Warm Beige - 
                            
                            #E7D6C1
                         - A subtle beige that provides a grounded, earthy feel.
6. Cool Lavender - 
                            
                            #D7C3E0
                         - A soothing lavender that introduces a hint of creativity.
7. Soft Coral - 
                            
                            #F2B2A0
                         - A light coral that is both vibrant and approachable.
8. Light Olive - 
                            
                            #B5C99A
                         - An understated olive green that brings a touch of nature.
9. Pale Yellow - 
                            
                            #F5E68D
                         - A soft yellow that adds brightness without overwhelming.
10. Slate Blue - 
                            
                            #6A8EAA
                         - A muted blue that conveys reliability and depth.
11. Terracotta - 
                            
                            #D4956D
                         - A warm, earthy tone that adds warmth and richness.
12. Seafoam - 
                            
                            #A7D3C6
                         - A refreshing and calming green-blue blend.
13. Charcoal Gray - 
                            
                            #4A4A4A
                         - A strong, dark gray that provides contrast and sophistication.
14. Dusty Turquoise - 
                            
                            #A0C7C6
                         - A muted turquoise that evokes feelings of tranquility.
15. Warm Taupe - 
                            
                            #C7B6A0
                         - An inviting taupe that adds warmth and neutrality.
16. Soft Plum - 
                            
                            #A77B9D
                         - A rich plum that offers elegance and depth.

Description:

This palette features muted, soft colors that create a professional yet inviting atmosphere. Each color is distinct enough to represent a different category while maintaining harmony throughout the spreadsheet.

Would you like to adjust any of the colors or need additional categories?