Examine source code of gray concrete road

{
  "name": "gray-concrete-road",
  "manifest_version": 2,
  "version": "1.0",
  "theme": {
    "images": {
      "theme_frame": "gray-concrete-road.png"
    },
    "colors": {
      "frame": "rgba(229, 230, 232, 1)",
      "tab_background_text": "rgba(52, 194, 219, 1)",
      "toolbar": "rgba(207, 195, 195, 1)",
      "bookmark_text": "rgba(40, 165, 219, 1)",
      "toolbar_field": "rgba(181, 181, 181, 1)",
      "toolbar_field_text": "rgba(2, 124, 138, 1)"
    }
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{557711d9-12f6-4306-9c30-c0881736c0b3}"
    }
  }
}