Examine source code of dark wood background

{
  "manifest_version": 2,
  "version": "1.0",
  "name": "dark wood",
  "theme": {
    "images": {
      "additional_backgrounds": [
        "images/0.jpg"
      ]
    },
    "properties": {
      "additional_backgrounds_alignment": [
        "right top"
      ],
      "additional_backgrounds_tiling": [
        "repeat"
      ]
    },
    "colors": {
      "toolbar": "rgba(243, 242, 240, 0)",
      "toolbar_text": "rgb(248, 248, 244)",
      "frame": "rgb(9, 12, 13)",
      "tab_background_text": "rgb(241, 236, 236)",
      "toolbar_field": "rgba(180, 180, 41, 0.01)",
      "toolbar_field_text": "rgb(239, 243, 244)",
      "tab_line": "rgb(248, 226, 112)",
      "popup": "rgb(71, 45, 15)",
      "popup_text": "rgb(244, 243, 238)",
      "tab_loading": "rgb(248, 226, 112)"
    }
  }
}