Examine source code of shugo chara.....

{
  "theme": {
    "images": {
      "theme_frame": "shugocharaff.jpg"
    },
    "colors": {
      "frame": "#94ffa8",
      "tab_background_text": "#94ffa8"
    }
  },
  "version": "2.0",
  "name": "shugo chara.....",
  "manifest_version": 2,
  "description": "shugo chara !"
}