Examine source code of DuckDuckGo Dark Mode

{
  "manifest_version": 2,
  "version": "1.0",
  "name": "DDG Dark Mode",
  "theme": {
    "images": {},
    "properties": {},
    "colors": {
      "toolbar": "rgb(28, 28, 28)",
      "toolbar_text": "rgb(238, 238, 238)",
      "frame": "rgb(22, 22, 22)",
      "tab_background_text": "rgb(204, 204, 204)",
      "toolbar_field": "rgb(51, 51, 51)",
      "toolbar_field_text": "rgb(238, 238, 238)",
      "tab_line": "rgb(40, 40, 40)",
      "popup": "rgb(28, 28, 28)",
      "popup_text": "rgb(204, 204, 204)",
      "button_background_active": "rgb(118, 157, 255)",
      "button_background_hover": "rgb(51, 51, 51)",
      "icons": "rgb(204, 204, 204)",
      "ntp_background": "rgb(22, 22, 22)",
      "ntp_text": "rgb(204, 204, 204)",
      "popup_border": "rgb(40, 40, 40)",
      "popup_highlight_text": "rgb(238, 238, 238)",
      "popup_highlight": "rgb(118, 157, 255)",
      "sidebar_border": "rgb(40, 40, 40)",
      "sidebar_highlight_text": "rgb(118, 157, 255)",
      "sidebar_highlight": "rgba(118, 157, 255, 0.1)",
      "sidebar_text": "rgb(204, 204, 204)",
      "tab_loading": "rgb(51, 51, 51)",
      "tab_selected": "rgb(28, 28, 28)",
      "tab_text": "rgb(238, 238, 238)",
      "toolbar_bottom_separator": "rgb(40, 40, 40)",
      "toolbar_field_border_focus": "rgb(118, 157, 255)",
      "toolbar_field_highlight_text": "rgb(118, 157, 255)",
      "toolbar_field_highlight": "rgba(118, 157, 255, 0.2)",
      "toolbar_field_text_focus": "rgb(238, 238, 238)",
      "toolbar_top_separator": "rgb(40, 40, 40)"
    }
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{68321f7e-fe52-49d8-8230-c815d6c64d47}"
    }
  }
}