Examine source code of Colorful pen

{
  "theme": {
    "images": {
      "theme_frame": "Colorfulpen-1.jpg"
    },
    "colors": {
      "frame": "#9ce0f7",
      "tab_background_text": "#f7f4f4"
    }
  },
  "version": "2.0",
  "name": "Colorful pen",
  "manifest_version": 2
}