gecko/browser/themes/windows/places/places-aero.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/. */

%include places.css

/* Style Places sidebars as Vista media collection */
@media (-moz-windows-default-theme) {
  #bookmarksPanel,
  #history-panel {
    background-color: #EEF3FA;
  }

  .sidebar-placesTree {
    background-color: transparent;
    border-top: none;
  }
}