Examine source code of TF2 Icon (simple, black)

{
  "theme": {
    "images": {
      "theme_frame": "header.png"
    },
    "colors": {
      "frame": "#545454",
      "tab_background_text": "#ff8426"
    }
  },
  "version": "2.0",
  "name": "TF2 Icon (simple, black)",
  "manifest_version": 2,
  "description": "A simple theme with the TF2 Icon on an entirely black backround."
}