Examine source code of Gray collage

{
  "theme": {
    "images": {
      "theme_frame": "Graycollage.jpg"
    },
    "colors": {
      "frame": "#c5f58b",
      "tab_background_text": "#f2f7f6"
    }
  },
  "version": "2.0",
  "name": "Gray collage",
  "manifest_version": 2,
  "description": "Another rose...gray and white this time."
}