Examine source code of Some Like it Dark

{
  "theme": {
    "images": {
      "theme_frame": "black-grade.png"
    },
    "colors": {
      "frame": "#000000",
      "tab_background_text": "#999999"
    }
  },
  "version": "2.0",
  "name": "Some Like it Dark",
  "manifest_version": 2,
  "description": "Some like it dark is a very minimalistic black/grey backgrounds with a med grey text."
}