Examine source code of Everforest base16

{
  "manifest_version": 2,
  "version": "1.0",
  "name": "Everforest base16",
  "theme": {
    "images": {
      "additional_backgrounds": [
        "images/bg-001-9c6d74e14860e77ee6f8f43e824bff25.svg"
      ]
    },
    "properties": {
      "additional_backgrounds_alignment": [
        "top"
      ],
      "additional_backgrounds_tiling": [
        "repeat"
      ]
    },
    "colors": {
      "toolbar": "rgb(54, 62, 68)",
      "toolbar_text": "rgb(211, 198, 170)",
      "frame": "rgb(40, 43, 44)",
      "tab_background_text": "rgb(130, 179, 168)",
      "toolbar_field": "rgb(46, 54, 60)",
      "toolbar_field_text": "rgb(244, 228, 192)",
      "tab_line": "rgb(167, 192, 128)",
      "popup": "rgb(34, 42, 48)",
      "popup_text": "rgb(131, 192, 146)",
      "button_background_hover": "rgb(34, 42, 48)",
      "icons": "rgb(220, 215, 186)",
      "ntp_background": "rgb(28, 36, 42)",
      "popup_border": "rgb(230, 126, 128)",
      "popup_highlight_text": "rgb(244, 243, 248)",
      "popup_highlight": "rgb(80, 88, 94)",
      "sidebar": "rgb(51, 59, 65)",
      "tab_loading": "rgb(0, 146, 255)",
      "toolbar_bottom_separator": "rgb(44, 47, 48)",
      "toolbar_field_border": "rgb(44, 47, 48)",
      "toolbar_top_separator": "rgb(44, 47, 48)",
      "toolbar_vertical_separator": "rgb(149, 209, 201)"
    }
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{3c80f23e-a695-483a-b9c3-0d35fe934b65}"
    }
  }
}