Examine source code of Pretty Evening Colours

{
  "manifest_version": 2,
  "version": "1.0",
  "name": "Pretty Pink",
  "theme": {
    "images": {
      "additional_backgrounds": [
        "images/0.png"
      ]
    },
    "properties": {
      "additional_backgrounds_alignment": [
        "center center"
      ],
      "additional_backgrounds_tiling": [
        "repeat"
      ]
    },
    "colors": {
      "toolbar": "rgb(1, 28, 71)",
      "toolbar_text": "rgb(248, 141, 142)",
      "frame": "rgb(8, 11, 33)",
      "tab_background_text": "rgb(215, 226, 239)",
      "toolbar_field": "rgb(29, 48, 94)",
      "toolbar_field_text": "rgb(245, 147, 161)",
      "tab_line": "rgb(229, 128, 143)",
      "popup": "rgb(31, 34, 61)",
      "popup_text": "rgb(248, 141, 142)",
      "toolbar_top_separator": "rgba(34, 25, 77, 0)",
      "tab_loading": "rgb(229, 128, 143)"
    }
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{dbe28789-d9f7-4330-96d3-0217fa2cc716}"
    }
  }
}