Here is a vibrant 70s rainbow color palette featuring 8 colors, designed for good contrast against a black background and sorted by hue:

json
{
  "palette_name": "70s Rainbow",
  "colors": [
    {
      "name": "Red",
      "hex_code": "
          
          #FF3D00
       "
    },
    {
      "name": "Orange",
      "hex_code": "
          
          #FF8F00
       "
    },
    {
      "name": "Yellow",
      "hex_code": "
          
          #FFC400
       "
    },
    {
      "name": "Green",
      "hex_code": "
          
          #76FF03
       "
    },
    {
      "name": "Light Blue",
      "hex_code": "
          
          #00B0FF
       "
    },
    {
      "name": "Blue",
      "hex_code": "
          
          #2979FF
       "
    },
    {
      "name": "Indigo",
      "hex_code": "
          
          #5C6BC0
       "
    },
    {
      "name": "Violet",
      "hex_code": "
          
          #AB47BC
       "
    }
  ]
}

This color palette captures the essence of the 70s with bold, bright colors that stand out beautifully against a black background.

Do you have any specific applications in mind for this palette, or would you like more variations or details?