Offline easter egg bug fixes

chrome/renderer/resources/neterror.css

 /* Copyright 2013 The Chromium Authors. All rights reserved.
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file. */
 
 /* Don't use the main frame div when the error is in a subframe. */
 html[subframe] #main-frame-error {
   display: none;
 }
 
 /* Don't use the subframe error div when the error is in a main frame. */
@@ skipping 316 matching lines @@
 }
 
 #buttons::after {
   clear: both;
   content: '';
   display: block;
   width: 100%;
 }
 
 /* Offline page */
+.offline {
+  transition: -webkit-filter 1.5s cubic-bezier(0.65, 0.05, 0.36, 1),
+              background-color 1.5s cubic-bezier(0.65, 0.05, 0.36, 1);
+  will-change: -webkit-filter, background-color;
+}
+
+.offline.inverted {
+  -webkit-filter: invert(100%);
+  background-color: #000;
+}
+
 .offline .interstitial-wrapper {
   color: #2b2b2b;
   font-size: 1em;
   line-height: 1.55;
   margin: 0 auto;
   max-width: 600px;
   padding-top: 100px;
   width: 100%;
 }
 
@@ skipping 107 matching lines @@
     overflow: inherit;
     padding: 0 8px;
   }
 }
 
 @media (max-width: 120px) {
   button {
     width: auto;
   }
 }