Examine source code of Vacuous Blue

{
  "theme": {
    "images": {
      "theme_frame": "header.png"
    },
    "colors": {
      "frame": "#000066",
      "tab_background_text": "#ffffff"
    }
  },
  "version": "2.0",
  "name": "Vacuous Blue",
  "manifest_version": 2,
  "description": "A simple dark blue theme that doesn't have a jarring edge with all in one sidebar; dark, but not pure black, it blends well with a blue task/title bar.  The patten is \"crack\" from GIMP 2.8's bucket fill tool re-colored and with some gradients applied."
}