Examine source code of Monochrome Simple

{
  "manifest_version": 2,
  "version": "1.0",
  "name": "Monochrome",
  "theme": {
    "images": {
      "additional_backgrounds": [
        "images/bg-000-5672c42860d5b06e1058dc477397f3ef.svg"
      ]
    },
    "properties": {
      "additional_backgrounds_alignment": [
        "top"
      ],
      "additional_backgrounds_tiling": [
        "repeat"
      ]
    },
    "colors": {
      "toolbar": "rgb(59, 59, 59)",
      "toolbar_text": "rgb(166, 166, 166)",
      "frame": "rgb(31, 31, 31)",
      "tab_background_text": "rgb(223, 223, 223)",
      "toolbar_field": "rgb(33, 33, 33)",
      "toolbar_field_text": "rgb(255, 255, 255)",
      "tab_line": "rgba(176, 176, 176, 0.38)",
      "popup": "rgb(68, 68, 68)",
      "popup_text": "rgb(189, 189, 189)",
      "tab_loading": "rgba(176, 176, 176, 0.38)"
    }
  }
}