Examine source code of chill red backround

{
  "manifest_version": 2,
  "version": "1.0",
  "name": "chill red backround",
  "theme": {
    "images": {
      "additional_backgrounds": [
        "images/bg-026-829b05416f823e170310e7c826ad1bec.svg"
      ]
    },
    "properties": {
      "additional_backgrounds_alignment": [
        "top"
      ],
      "additional_backgrounds_tiling": [
        "repeat"
      ]
    },
    "colors": {
      "toolbar": "rgb(52, 23, 25)",
      "toolbar_text": "rgb(162, 45, 45)",
      "frame": "rgb(86, 13, 15)",
      "tab_background_text": "rgb(255, 0, 0)",
      "toolbar_field": "rgb(0, 0, 0)",
      "toolbar_field_text": "rgb(255, 116, 116)",
      "tab_line": "rgb(105, 13, 13)",
      "popup": "rgb(45, 27, 27)",
      "popup_text": "rgb(255, 0, 21)",
      "tab_loading": "rgb(105, 13, 13)"
    }
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{da3c7824-6ea4-464c-900f-c746a92c5df3}"
    }
  }
}