Examine source code of A little blue

{
  "manifest_version": 2,
  "version": "1.0",
  "name": "A little",
  "theme": {
    "images": {
      "additional_backgrounds": [
        "images/0.png"
      ]
    },
    "properties": {
      "additional_backgrounds_alignment": [
        "left bottom"
      ],
      "additional_backgrounds_tiling": [
        "no-repeat"
      ]
    },
    "colors": {
      "toolbar": "rgb(166, 83, 98)",
      "toolbar_text": "rgb(255, 255, 255)",
      "frame": "rgb(7, 34, 115)",
      "tab_background_text": "rgb(217, 217, 217)",
      "toolbar_field": "rgb(191, 159, 159)",
      "toolbar_field_text": "rgb(38, 38, 38)",
      "tab_line": "rgb(242, 213, 196)",
      "popup": "rgb(217, 217, 217)",
      "popup_text": "rgb(38, 38, 38)",
      "tab_loading": "rgb(242, 213, 196)"
    }
  }
}