Examine source code of Simple gray elegant

{
  "name": "Simple gray elegant",
  "manifest_version": 2,
  "version": "1.0",
  "theme": {
    "images": {
      "theme_frame": "gray.png"
    },
    "colors": {
      "frame": "rgba(40, 40, 40, 1)",
      "tab_background_text": "rgba(170, 170, 170, 1)",
      "toolbar": "rgba(80, 80, 80, 1)",
      "toolbar_field_text": "rgba(170, 170, 170, 1)",
      "tab_line": "rgba(103, 179, 191, 1)"
    }
  }
}