Examine source code of Black Theme

{
  "name": "Black Theme",
  "manifest_version": 2,
  "version": "2.0",
  "theme": {
    "images": {
      "theme_frame": "036_smiling_face_with_horns.png"
    },
    "colors": {
      "frame": "rgba(46, 46, 46, 1)",
      "tab_background_text": "rgba(214, 214, 214, 1)",
      "toolbar": "rgba(33, 33, 33, 1)",
      "bookmark_text": "rgba(212, 212, 212, 1)",
      "toolbar_field": "rgba(69, 69, 69, 1)",
      "toolbar_field_text": "rgba(214, 214, 214, 1)"
    }
  }
}