gecko-dev/browser/themes/osx/searchbar.css

/* This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

.searchbar-textbox {
  border-radius: 10000px;
}

.searchbar-engine-button {
  -moz-padding-start: 6px;
  -moz-padding-end: 2px;
  margin: 0;
  -moz-margin-end: 2px;
  -moz-appearance: none;
  min-width: 0;
}

.searchbar-popup {
  margin-top: 4px;
  -moz-margin-start: 3px;
}

.searchbar-textbox > .autocomplete-textbox-container > .textbox-input-box {
  margin: 0;
  padding: 3px 0 2px;
  height: 20px;
}

.searchbar-engine-image {
  width: 16px;
  height: 16px;
  list-style-image: url("chrome://mozapps/skin/places/defaultFavicon.png");
}

.searchbar-dropmarker-image {
  list-style-image: url("chrome://browser/skin/searchbar-dropmarker.png");
  -moz-margin-start: 2px;
}

.search-go-container {
  -moz-box-align: center;
  -moz-padding-end: 6px;
}

.search-go-button {
  list-style-image: url("chrome://browser/skin/Search.png");
}

@media (min-resolution: 2dppx) {
  .searchbar-engine-image,
  .searchbar-engine-menuitem > .menu-iconic-left > .menu-iconic-icon {
    image-rendering: -moz-crisp-edges;
  }

  .searchbar-engine-image {
    list-style-image: url("chrome://mozapps/skin/places/defaultFavicon@2x.png");
  }

  .searchbar-dropmarker-image {
    list-style-image: url("chrome://browser/skin/searchbar-dropmarker@2x.png");
    width: 7px;
  }

  .search-go-button {
    list-style-image: url("chrome://browser/skin/Search@2x.png");
    width: 14px;
  }
}