Examine source code of Sunset Theme by imtonie

{
  "theme": {
    "images": {
      "theme_frame": "header.png"
    },
    "colors": {
      "frame": "#4f4f4f",
      "tab_background_text": "#ffffff"
    }
  },
  "version": "2.0",
  "name": "Sunset Theme by imtonie",
  "manifest_version": 2,
  "description": "\"Sunset\" by <a rel=\"nofollow\" href=\"https://addons.mozilla.org/en-US/firefox/user/imtonie/\"> imtonie</a>.\n\nFeel free to use but give credit to me. :)\n\n(If you want a specific theme just write a review/comment with it)"
}