Sure! To complement the colors #172528 (deep teal) and #d2d550 (muted yellow), I suggest adding #4b6f8c , a cool, muted slate blue. This color will provide a nice balance while maintaining a calm and sophisticated vibe.

Here is the updated color palette in JSON format:

json
{
  "palette_name": "Calm Essence",
  "colors": [
    {
      "name": "Deep Teal",
      "hex_code": "
                            
                            #172528
                        "
    },
    {
      "name": "Muted Yellow",
      "hex_code": "
                            
                            #d2d550
                        "
    },
    {
      "name": "Slate Blue",
      "hex_code": "
                            
                            #4b6f8c
                        "
    }
  ]
}

This palette presents a serene combination of colors, where the deep teal anchors the palette, the muted yellow adds brightness, and the slate blue introduces a tranquil contrast. Would you like to see more options or perhaps focus on a different theme?