Examine source code of Pikachu Dark Theme

{
  "manifest_version": 2,
  "version": "1.0",
  "name": "Pikachu Dark theme",
  "theme": {
    "images": {
      "additional_backgrounds": [
        "images/0.jpg"
      ]
    },
    "properties": {
      "additional_backgrounds_alignment": [
        "right center"
      ],
      "additional_backgrounds_tiling": [
        "no-repeat"
      ]
    },
    "colors": {
      "toolbar": "rgba(47, 52, 63, 0)",
      "toolbar_text": "rgba(225, 234, 239, 0.9)",
      "frame": "rgb(47, 52, 63)",
      "tab_background_text": "rgb(152, 152, 155)",
      "toolbar_field": "rgb(51, 51, 51)",
      "toolbar_field_text": "rgba(225, 234, 239, 0.7)",
      "tab_line": "rgba(152, 152, 155, 0.7)",
      "popup": "rgb(47, 52, 63)",
      "popup_text": "rgba(225, 234, 239, 0.7)",
      "tab_loading": "rgba(152, 152, 155, 0.7)"
    }
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{112735fe-7b32-4920-b07f-74c5074d1587}"
    }
  }
}