Examine source code of Subtle Blues

{
  "theme": {
    "images": {
      "theme_frame": "subtle-blues.png"
    },
    "colors": {
      "frame": "#999999",
      "tab_background_text": "#333333"
    }
  },
  "version": "2.0",
  "name": "Subtle Blues",
  "manifest_version": 2,
  "description": "Soft blues with accent lighting"
}