Examine source code of gray squares 100

{
  "theme": {
    "images": {
      "theme_frame": "squareshead.jpg"
    },
    "colors": {
      "frame": "#272396",
      "tab_background_text": "#ff0000"
    }
  },
  "version": "2.0",
  "name": "gray squares 100",
  "manifest_version": 2,
  "description": "gray squares"
}