issue 1435 - Port popup.html from Chrome/Safari/Opera to Firefox

chrome/skin/popup.css

 /*
  * This file is part of Adblock Plus <http://adblockplus.org/>,
  * Copyright (C) 2006-2014 Eyeo GmbH
  *
  * Adblock Plus is free software: you can redistribute it and/or modify
  * it under the terms of the GNU General Public License version 3 as
  * published by the Free Software Foundation.
  *
  * Adblock Plus is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
@@ skipping 60 matching lines @@
 {
   min-width: 150px;
   cursor: pointer;
   padding: 10px 35px;
   border-top: 1px solid #e1ddd8;
   background-image: url(background-main.png);
 }
 
 footer:hover
 {
-  background: -webkit-linear-gradient(top, rgba(70, 50, 0, 0.1), rgba(70, 50, 0, 0.1)),
-    url(background-main.png);
   background: linear-gradient(to bottom, rgba(70, 50, 0, 0.1), rgba(70, 50, 0, 0.1)),
     url(background-main.png);
 }
 
 footer .icon
 {
   background-position: -50px -65px;
 }
 
 ul
@@ skipping 66 matching lines @@
 #clickhide-instructions
 {
   margin: 10px 15px;
 }
 
 #blockable .icon
 {
   background-position: -66px -17px;
 }
 
+#blockable:not(.open) [data-action="close"],
+#blockable.open [data-action="open"]
+{
+  display: none;
+}
+
 #report-issue .icon
 {
   background-position: -50px -81px;
 }
 
 label
 {
   vertical-align: middle;
 }