Examine source code of Vintage Miku

{
  "theme": {
    "images": {
      "theme_frame": "mikuHeader_LABS.jpg"
    },
    "colors": {
      "frame": "#404040",
      "tab_background_text": "#1c0303"
    }
  },
  "version": "2.0",
  "name": "Vintage Miku",
  "manifest_version": 2,
  "description": "My first persona *.* Hope you like it XD\n\nVocaloid, Miku Hatsune, blue, anime girl, bege, lolita."
}