Examine source code of Beijing Night

{
  "theme": {
    "images": {
      "theme_frame": "BeiJing_night_header.jpg"
    },
    "colors": {
      "frame": "#f5f0f0",
      "tab_background_text": "#fafafa"
    }
  },
  "version": "2.0",
  "name": "Beijing Night",
  "manifest_version": 2
}