Here’s a refined color palette that emphasizes more distinct darker colors with contrasting characteristics to ensure they stand out from one another:

json
{
  "palette_name": "Diverse Dark Quartet",
  "colors": [
    {
      "name": "Midnight Blue",
      "hex_code": "
                            
                            #2C3E50
                        "
    },
    {
      "name": "Deep Cerulean",
      "hex_code": "
                            
                            #005C99
                        "
    },
    {
      "name": "Dark Magenta",
      "hex_code": "
                            
                            #8E44AD
                        "
    },
    {
      "name": "Forest Green",
      "hex_code": "
                            
                            #1B5E20
                        "
    }
  ]
}

This palette features a variety of darker, more distinct colors, each with its own unique identity while maintaining a contrasting relationship. The combination of blue, green, and purple tones ensures that each color is visually distinct and adds vibrancy.

Would you like to explore further adjustments or applications for this palette in your design projects?