Examine source code of Dark

{
  "manifest_version": 2,
  "version": "1.3",
  "name": "Dark",
  "theme": {
    "colors": {
      "frame": "rgb(15, 15, 15)",
      "tab_background_text": "rgb(153, 153, 153)",
      "tab_text": "rgb(215, 226, 239)",
      "tab_selected": "rgb(18, 18, 18)",
      "tab_line": "rgb(215, 226, 239)",
      "tab_loading": "rgb(55, 55, 55)",
      "toolbar": "rgb(32, 32, 32)",
      "toolbar_text": "rgb(215, 226, 239)",
      "toolbar_field": "rgb(18, 18, 18)",
      "toolbar_field_text": "rgb(215, 226, 239)",
      "toolbar_field_border": "rgb(55, 55, 55)",
      "toolbar_field_border_focus": "rgb(55, 55, 55)",
      "toolbar_top_separator": "rgb(15, 15, 15)",
      "toolbar_bottom_separator": "rgb(15, 15, 15)",
      "toolbar_vertical_separator": "rgb(15, 15, 15)",
      "popup": "rgb(24, 24, 24)",
      "popup_text": "rgb(215, 226, 239)",
      "popup_border": "rgb(55, 55, 55)",
      "button_background_active": "rgb(18, 18, 18)",
      "button_background_hover": "rgb(24, 24, 24)",
      "icons": "rgb(215, 226, 239)",
      "sidebar": "rgb(15, 15, 15)",
      "sidebar_text": "rgb(215, 226, 239)",
      "sidebar_border": "rgb(55, 55, 55)",
      "ntp_text": "rgba(215, 226, 239, 0.5)",
      "ntp_background": "rgb(15, 15, 15)"
    }
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{1ba6c5ad-4144-4f55-a9d6-55d58b4c0503}"
    }
  }
}