Examine source code of Gruvbox Dark Theme

{
  "manifest_version": 2,
  "name": "Gruvbox Dark",
  "description": "Gruvbox dark theme for Firefox.",
  "version": "1.1",
  "theme": {
    "colors": {
      "frame": "#1d2021",
      "frame_inactive": "#282828",
      "toolbar": "#282828",
      "toolbar_top_separator": "#282828",
      "toolbar_vertical_separator": "#a89984",
      "toolbar_bottom_separator": "#282828",
      "tab_background_separator": "#3c3836",
      "tab_background_text": "#d5c4a1",
      "tab_text": "#ebdbb2",
      "tab_line": "#fe8019",
      "tab_loading": "#fe8019",
      "bookmark_text": "#ebdbb2",
      "sidebar": "#32302f",
      "sidebar_text": "#ebdbb2",
      "sidebar_highlight_text": "#ebdbb2",
      "sidebar_highlight": "#458588",
      "sidebar_border": "#fe8019",
      "toolbar_field": "#3c3836",
      "toolbar_field_focus": "#504945",
      "toolbar_field_border": "#32302f",
      "toolbar_field_border_focus": "#fe8019",
      "toolbar_field_highlight": "#83a598",
      "toolbar_field_highlight_text": "#ebdbb2",
      "toolbar_field_text": "#d5c4a1",
      "toolbar_field_text_focus": "#ebdbb2",
      "popup": "#3c3836",
      "popup_text": "#ebdbb2",
      "popup_border": "#3c3836",
      "popup_highlight": "#458588",
      "popup_highlight_text": "#ebdbb2",
      "ntp_background": "#32302f",
      "ntp_text": "#ebdbb2"
    }
  }
}