Examine source code of Graphite Grey UI

{
  "manifest_version": 2,
  "version": "1.0",
  "name": "Graphite Grey UI",
  "theme": {
    "images": {
      "additional_backgrounds": [
        "images/bg-002-609370e89a219e0548ac5ef6b4a7dd2e.svg"
      ]
    },
    "properties": {
      "additional_backgrounds_alignment": [
        "top"
      ],
      "additional_backgrounds_tiling": [
        "repeat"
      ]
    },
    "colors": {
      "toolbar": "rgb(215, 220, 225)",
      "toolbar_text": "rgb(0, 0, 0)",
      "frame": "rgb(145, 155, 165)",
      "tab_background_text": "rgb(0, 0, 0)",
      "toolbar_field": "rgb(245, 247, 248)",
      "toolbar_field_text": "rgb(0, 0, 0)",
      "tab_line": "rgba(145, 155, 165, 0.43)",
      "popup": "rgb(215, 220, 225)",
      "popup_text": "rgb(0, 0, 0)",
      "ntp_background": "rgb(215, 220, 225)",
      "popup_border": "rgb(145, 155, 165)",
      "sidebar_border": "rgb(145, 155, 165)",
      "sidebar": "rgb(215, 220, 225)",
      "tab_loading": "rgba(145, 155, 165, 0.43)"
    }
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{efe94b9f-c6af-4b6e-aeab-3fe83afc6ff7}"
    }
  }
}