Examine source code of Heart Attack

{
  "theme": {
    "images": {
      "theme_frame": "heartheader.jpg"
    },
    "colors": {
      "frame": "#fcf4f4",
      "tab_background_text": "#f7f2f2"
    }
  },
  "version": "2.0",
  "name": "Heart Attack",
  "manifest_version": 2,
  "description": "Hearts & sparkles"
}