Examine source code of Gray Theme

{
  "theme": {
    "images": {
      "theme_frame": "Untitled-1.png"
    },
    "colors": {
      "frame": "#a1a1a1",
      "tab_background_text": "#bac"
    }
  },
  "version": "2.0",
  "name": "Gray Theme",
  "manifest_version": 2,
  "description": "Gray Theme"
}