Here is an expanded color palette with 11 colors inspired by the Outlook mail theme:

json
{
  "palette_name": "Extended Outlook Mail Theme",
  "colors": [
    {
      "name": "Sky Blue",
      "hex_code": "
          
          #0072C6
       "
    },
    {
      "name": "Light Gray",
      "hex_code": "
          
          #F3F3F3
       "
    },
    {
      "name": "White",
      "hex_code": "
          
          #FFFFFF
       "
    },
    {
      "name": "Dark Gray",
      "hex_code": "
          
          #3B3B3B
       "
    },
    {
      "name": "Accent Blue",
      "hex_code": "
          
          #005EB8
       "
    },
    {
      "name": "Soft Green",
      "hex_code": "
          
          #A8DAB5
       "
    },
    {
      "name": "Warm Beige",
      "hex_code": "
          
          #F5E1A4
       "
    },
    {
      "name": "Coral Red",
      "hex_code": "
          
          #FF6F61
       "
    },
    {
      "name": "Slate Blue",
      "hex_code": "
          
          #6A9BD1
       "
    },
    {
      "name": "Charcoal Black",
      "hex_code": "
          
          #2A2A2A
       "
    },
    {
      "name": "Muted Lavender",
      "hex_code": "
          
          #E0C7E0
       "
    }
  ]
}

This extended palette maintains the professional feel of the Outlook mail interface while introducing additional colors that can provide versatility, such as soft green and coral red for a touch of warmth.

Would you like any specific suggestions on how to utilize these colors, or do you have other requests?