Examine source code of Crazy Train

{
  "theme": {
    "images": {
      "theme_frame": "header.png"
    },
    "colors": {
      "frame": "#423838",
      "tab_background_text": "#ffffff"
    }
  },
  "version": "2.0",
  "name": "Crazy Train",
  "manifest_version": 2,
  "description": "A manipulated train image with the addition of a face and an interesting use of layering. It may be hard to tell this is a train."
}