Examine source code of drawing board

{
  "theme": {
    "images": {
      "theme_frame": "header.png"
    },
    "colors": {
      "frame": "#226ab2",
      "tab_background_text": "#ffffff"
    }
  },
  "version": "2.0",
  "name": "drawing board",
  "manifest_version": 2,
  "description": "Studies suggest that blue color boosts creativity. That is when I thought about such a theme. The small checks make it look more apealing"
}