Examine source code of Dark

{
  "manifest_version": 2,
  "version": "1.0",
  "name": "Autumn Twining",
  "theme": {
    "images": {
      "additional_backgrounds": []
    },
    "properties": {
      "additional_backgrounds_alignment": [],
      "additional_backgrounds_tiling": []
    },
    "colors": {
      "toolbar": "rgba(15, 20, 40, 0.65)",
      "toolbar_text": "rgb(255, 255, 255)",
      "frame": "rgb(36, 40, 59)",
      "tab_background_text": "rgb(235, 255, 255)",
      "toolbar_field": "rgba(21, 27, 51, 0.98)",
      "toolbar_field_text": "rgb(255, 255, 255)",
      "tab_line": "rgb(36, 40, 59)",
      "popup": "rgba(21, 27, 51, 0.98)",
      "popup_text": "rgb(244, 244, 244)",
      "ntp_background": "rgb(28, 28, 45)",
      "ntp_text": "rgba(205, 215, 255, 0.6)",
      "popup_border": "rgba(163, 174, 222, 0)",
      "popup_highlight_text": "rgb(29, 19, 19)",
      "popup_highlight": "rgb(193, 245, 245)",
      "sidebar_border": "rgba(0, 45, 255, 0)",
      "sidebar": "rgb(28, 28, 45)",
      "tab_loading": "rgba(50, 222, 253, 0)",
      "tab_text": "rgb(62, 255, 255)",
      "toolbar_field_highlight": "rgb(120, 145, 245)"
    }
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{d470e2a3-6538-4b76-938e-252ce9d8c058}"
    }
  }
}