Examine source code of Custom Dark Red Theme

{
  "manifest_version": 2,
  "name": "Dark Red Theme",
  "version": "1.1",
  "description": "A theme with dark red color scheme",
  "browser_specific_settings": {
    "gecko": {
      "id": "darkredtheme@yourdomain.com"
    }
  },
  "theme": {
    "colors": {
      "frame": "#742222",
      "tab_background_text": "#ebe1d5",
      "toolbar": "#191919",
      "toolbar_text": "#ebe1d5",
      "toolbar_field": "#2b2b2b",
      "toolbar_field_text": "#ebe1d5",
      "tab_selected": "#521818",
      "tab_text": "#ebe1d5",
      "popup": "#191919",
      "popup_text": "#ebe1d5",
      "button_background_active": "#742222",
      "button_background_hover": "#742222",
      "tab_line": "#521818"
    }
  }
}