Here is an expanded color palette for data visualization with seven colors, including your specified colors ( #00205B and #00B2E3 ) and maintaining the cool color theme:

json
{
  "palette_name": "Extended Cool Blues Palette",
  "colors": [
    {
      "name": "Dark Blue",
      "hex_code": "
          
          #00205B
       "
    },
    {
      "name": "Sky Blue",
      "hex_code": "
          
          #00B2E3
       "
    },
    {
      "name": "Light Blue",
      "hex_code": "
          
          #ADD8E6
       "
    },
    {
      "name": "Navy",
      "hex_code": "
          
          #001F3F
       "
    },
    {
      "name": "Teal",
      "hex_code": "
          
          #008080
       "
    },
    {
      "name": "Cyan",
      "hex_code": "
          
          #00FFFF
       "
    },
    {
      "name": "Steel Blue",
      "hex_code": "
          
          #4682B4
       "
    }
  ]
}

This palette now includes seven shades of blue and cyan, offering a diverse range of colors suitable for clear and effective data visualization.

Is there anything else you would like to adjust or any additional requirements you have?