Examine source code of Astolfo dark-ish ?

{
  "manifest_version": 2,
  "version": "1.0",
  "name": "Astolfo dark-ish ?",
  "theme": {
    "images": {
      "additional_backgrounds": [
        "images/0.png"
      ]
    },
    "properties": {
      "additional_backgrounds_alignment": [
        "left center"
      ],
      "additional_backgrounds_tiling": [
        "no-repeat"
      ]
    },
    "colors": {
      "toolbar": "rgb(0, 0, 0)",
      "toolbar_text": "rgb(203, 106, 190)",
      "frame": "rgb(158, 109, 131)",
      "tab_background_text": "rgb(37, 26, 37)",
      "toolbar_field": "rgb(37, 26, 37)",
      "toolbar_field_text": "rgb(212, 175, 55)",
      "tab_line": "rgb(203, 106, 190)",
      "popup": "rgb(37, 26, 37)",
      "popup_text": "rgb(203, 106, 190)",
      "ntp_background": "rgb(0, 0, 0)",
      "ntp_text": "rgb(203, 106, 190)",
      "tab_background_separator": "rgb(203, 106, 190)",
      "tab_text": "rgb(203, 106, 190)",
      "tab_loading": "rgb(203, 106, 190)"
    }
  }
}