Here’s an updated color palette for your Gantt chart in Excel. The subheader color has been changed to differentiate it from the header, and I’ve added more item colors for additional variety.

json
{
  "palette_name": "Gantt Chart Colors Updated",
  "colors": [
    {
      "name": "Title Header",
      "hex_code": "
          
          #4A4A4A
       "
    },
    {
      "name": "Subheader",
      "hex_code": "
          
          #A9A9A9
       "
    },
    {
      "name": "Item Color 1",
      "hex_code": "
          
          #FF6F61
       "
    },
    {
      "name": "Item Color 2",
      "hex_code": "
          
          #6B5B93
       "
    },
    {
      "name": "Item Color 3",
      "hex_code": "
          
          #88B04B
       "
    },
    {
      "name": "Item Color 4",
      "hex_code": "
          
          #F7CAC9
       "
    },
    {
      "name": "Item Color 5",
      "hex_code": "
          
          #92A8D1
       "
    },
    {
      "name": "Item Color 6",
      "hex_code": "
          
          #955251
       "
    },
    {
      "name": "Item Color 7",
      "hex_code": "
          
          #E8C547
       "
    },
    {
      "name": "Item Color 8",
      "hex_code": "
          
          #D95B43
       "
    },
    {
      "name": "Item Color 9",
      "hex_code": "
          
          #C7B9E1
       "
    },
    {
      "name": "Item Color 10",
      "hex_code": "
          
          #F2A3B9
       "
    }
  ]
}

In this palette, the subheader is now a distinct shade of gray, providing a clear separation from the title header. Additionally, I’ve included four more item colors to enhance the visual variety of your Gantt chart.

Would you like any further modifications or additions?