Examine source code of Polar Green Gradient

{
  "manifest_version": 2,
  "version": "1.0",
  "name": "Polar Green Gradient",
  "theme": {
    "images": {
      "additional_backgrounds": [
        "images/0.jpg"
      ]
    },
    "properties": {
      "additional_backgrounds_alignment": [
        "center center"
      ],
      "additional_backgrounds_tiling": [
        "repeat"
      ]
    },
    "colors": {
      "toolbar": "rgba(59, 94, 59, 0)",
      "toolbar_text": "rgb(200, 200, 200)",
      "frame": "rgb(0, 0, 0)",
      "tab_background_text": "rgb(187, 187, 187)",
      "toolbar_field": "rgba(10, 33, 12, 0)",
      "toolbar_field_text": "rgb(223, 223, 223)",
      "tab_line": "rgb(187, 187, 187)",
      "popup": "rgb(10, 33, 12)",
      "popup_text": "rgb(184, 184, 184)",
      "ntp_background": "rgb(0, 0, 0)",
      "tab_loading": "rgb(187, 187, 187)"
    }
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{835c516f-1461-480b-b186-9d1e3c00942c}"
    }
  }
}