Examine source code of skyblue theme

{
  "manifest_version": 2,
  "version": "1.0",
  "name": "skyblue theme",
  "theme": {
    "images": {
      "additional_backgrounds": [
        "images/0.jpg"
      ]
    },
    "properties": {
      "additional_backgrounds_alignment": [
        "right top"
      ],
      "additional_backgrounds_tiling": [
        "repeat"
      ]
    },
    "colors": {
      "toolbar": "rgb(52, 50, 50)",
      "toolbar_text": "rgb(55, 251, 235)",
      "frame": "rgb(57, 51, 51)",
      "tab_background_text": "rgb(15, 151, 147)",
      "toolbar_field": "rgb(174, 177, 177)",
      "toolbar_field_text": "rgb(15, 151, 147)",
      "tab_line": "rgb(61, 230, 167)",
      "popup": "rgb(57, 51, 51)",
      "popup_text": "rgb(15, 151, 147)",
      "tab_loading": "rgb(61, 230, 167)"
    }
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{709e4926-2daf-4c3b-9e2f-7fc1db5eb919}"
    }
  }
}