Examine source code of Developer Edition V1

{
  "manifest_version": 2,
  "version": "1.0",
  "name": "Developer Edition",
  "theme": {
    "images": {
      "additional_backgrounds": [
        "images/bg-001-9c6d74e14860e77ee6f8f43e824bff25.svg"
      ]
    },
    "properties": {
      "additional_backgrounds_alignment": [
        "top"
      ],
      "additional_backgrounds_tiling": [
        "repeat"
      ]
    },
    "colors": {
      "toolbar": "rgb(8, 3, 53)",
      "toolbar_text": "rgb(0, 255, 249)",
      "frame": "rgb(29, 4, 79)",
      "tab_background_text": "rgb(24, 156, 180)",
      "toolbar_field": "rgb(29, 29, 75)",
      "toolbar_field_text": "rgb(66, 225, 254)",
      "tab_line": "rgb(255, 0, 46)",
      "popup": "rgb(0, 0, 0)",
      "popup_text": "rgb(16, 241, 92)",
      "button_background_active": "rgb(17, 23, 184)",
      "button_background_hover": "rgb(16, 59, 59)",
      "tab_text": "rgb(255, 0, 0)",
      "toolbar_bottom_separator": "rgb(17, 23, 184)",
      "toolbar_field_border_focus": "rgb(255, 0, 3)",
      "toolbar_field_border": "rgb(255, 0, 4)",
      "toolbar_field_highlight_text": "rgb(29, 4, 79)",
      "toolbar_field_highlight": "rgb(255, 0, 46)",
      "toolbar_field_separator": "rgb(255, 0, 4)",
      "toolbar_field_text_focus": "rgb(66, 225, 254)",
      "toolbar_top_separator": "rgb(255, 0, 46)",
      "tab_loading": "rgb(255, 0, 46)"
    }
  }
}