Examine source code of Dark Mode

{
  "manifest_version": 2,
  "version": "1.0",
  "name": "Complimentary Dark Mode",
  "theme": {
    "images": {
      "additional_backgrounds": [
        "images/bg-023-f741aad3989b46322a7840a425068429.svg"
      ]
    },
    "properties": {
      "additional_backgrounds_alignment": [
        "top"
      ],
      "additional_backgrounds_tiling": [
        "repeat"
      ]
    },
    "colors": {
      "toolbar": "rgb(32, 32, 32)",
      "toolbar_text": "rgb(255, 255, 255)",
      "frame": "rgb(12, 12, 12)",
      "tab_background_text": "rgb(255, 255, 255)",
      "toolbar_field": "rgb(53, 53, 53)",
      "toolbar_field_text": "rgb(255, 255, 255)",
      "tab_line": "rgba(0, 124, 255, 0)",
      "popup": "rgb(32, 32, 32)",
      "popup_text": "rgb(255, 255, 255)",
      "frame_inactive": "rgb(0, 0, 0)",
      "toolbar_top_separator": "rgb(53, 53, 53)",
      "tab_loading": "rgba(0, 124, 255, 0)"
    }
  }
}