Examine source code of airplane3

{
  "manifest_version": 2,
  "version": "1.0",
  "name": "airplane3",
  "theme": {
    "images": {
      "additional_backgrounds": [
        "images/0.jpg",
        "images/1.jpg",
        "images/2.jpg"
      ]
    },
    "properties": {
      "additional_backgrounds_alignment": [
        "left bottom",
        "center center",
        "right top"
      ],
      "additional_backgrounds_tiling": [
        "repeat-y",
        "repeat-y",
        "repeat-y"
      ]
    },
    "colors": {
      "toolbar": "rgba(203, 203, 213, 0.29)",
      "toolbar_text": "rgb(255, 255, 255)",
      "frame": "rgb(232, 230, 244)",
      "tab_background_text": "rgb(0, 0, 255)",
      "toolbar_field": "rgba(202, 199, 225, 0.29)",
      "toolbar_field_text": "rgb(14, 14, 228)",
      "tab_line": "rgb(14, 14, 228)",
      "popup": "rgb(70, 75, 92)",
      "popup_text": "rgb(232, 230, 244)",
      "tab_loading": "rgb(14, 14, 228)"
    }
  }
}