Examine source code of Solar, sunny

{
  "manifest_version": 2,
  "version": "1.0",
  "name": "Solar energy",
  "theme": {
    "images": {
      "additional_backgrounds": [
        "images/0.jpg"
      ]
    },
    "properties": {
      "additional_backgrounds_alignment": [
        "center center"
      ],
      "additional_backgrounds_tiling": [
        "repeat"
      ]
    },
    "colors": {
      "toolbar": "rgba(231, 224, 211, 0.5)",
      "toolbar_text": "rgb(125, 87, 17)",
      "frame": "rgb(251, 249, 245)",
      "tab_background_text": "rgb(80, 56, 16)",
      "toolbar_field": "rgb(251, 249, 245)",
      "toolbar_field_text": "rgb(80, 56, 16)",
      "tab_line": "rgb(235, 177, 15)",
      "popup": "rgb(251, 249, 245)",
      "popup_text": "rgb(125, 87, 17)",
      "ntp_background": "rgba(231, 224, 211, 0.5)",
      "ntp_text": "rgb(80, 56, 16)",
      "tab_loading": "rgb(235, 177, 15)"
    }
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{d99a6c95-f94e-44d6-b84c-586cbef9b8d7}"
    }
  }
}