The updated (simplified) look of set-as-default dialog on Windows8.

chrome/browser/resources/set_as_default_browser.css

 /* Copyright (c) 2012 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. */
 
 /* The main (outer) container. */
 #metro-setup-outer-container {
   -webkit-box-align: center;
   -webkit-box-orient: vertical;
-  -webkit-box-pack: center;
+  -webkit-box-pack: start;
   -webkit-transition: 200ms opacity;
   background-color: rgba(255, 255, 255, 0.75);
   bottom: 0;
   display: -webkit-box;
   left: 0;
   overflow: auto;
-  padding: 20px;
   position: fixed;
   right: 0;
   top: 0;
 }
 
 /* The page block within the outer container. */
 #metro-setup-outer-container .page {
   -webkit-border-radius: 3px;
   -webkit-box-orient: vertical;
   -webkit-user-select: none;
   background: white;
   background-color: white;
   color: #333;
   display: -webkit-box;
-  margin-bottom: 6px;
-  margin-top: 6px;
   min-width: 400px;
-  padding: 0;
+  padding-top: 70pt;

[James Hawkins, 2012/08/03 22:51:44]

pt?  We don't usually use pt, so can you use px instead?

[motek., 2012/08/06 18:38:30]

Done.

   position: relative;
-  width: 400px;
+  width: 500px;
 }
 
 #metro-setup-outer-container .page .content-area {
   -webkit-box-flex: 1;
+  margin: 0;
   overflow: auto;
-  padding: 6px 17px 26px;
+  padding: 0;
 }
 
 #metro-setup-overlay {
   background-color: transparent;
   margin: 0;
   width: 100%;
 }
 
 /* Page Title. */
 #metro-title-container {
   display: block;
   margin: 37px 44px 35px;
   text-align: center;
 }
 
 #metro-setup-outer-container .page h1 {
   border-bottom: 0;
-  color: rgb(34, 34, 34);
-  font-size: 340%;
+  color: #323232;
+  font-size: 28pt;

[James Hawkins, 2012/08/03 22:51:44]

font-size needs to be relative, not absolute.

[motek., 2012/08/06 18:38:30]

Done.

   font-weight: normal;
   margin: 0;
   padding-bottom: 0;
-  padding-top: 13px;
+  padding-top: 0;
   text-align: center;
 }
 
 #metro-setup-outer-container .page h2 {
   border-bottom: 0;
-  color: rgb(102, 102, 102);
-  font-size: 160%;
+  color: #787878;
+  font-size: 14pt;

[James Hawkins, 2012/08/03 22:51:44]

Relative, not absolute.

[motek., 2012/08/06 18:38:30]

Done.

   font-weight: normal;
+  margin-bottom: 4.9em;

[James Hawkins, 2012/08/03 22:51:44]

Any reason we're using em here and px elsewhere?

[motek., 2012/08/06 18:38:30]

Not really. I mean: there was a reason. I got a mock for the new look & feel
that was spec'd in a funny way and it was just more convenient for me to express
it as proportions, even though originally it was all pixels. It reduces itself
to pixels, so there it is...

+  margin-top: 0.75em;
   text-align: center;
 }
 
 #metro-setup-overlay .content-area {
   padding: 10px 15px;
   text-align: end;
 }
 
 /* Action buttons. */
 #metro-action-box button {
@@ skipping 55 matching lines @@
   border-color: rgb(47, 91, 183);
   color: white;
 }
 
 #metro-action-box #launch-button:focus {
   border-color: rgb(77, 144, 254);
   outline: none;
   z-index: 4 !important;
 }
 
-#metro-action-box #return-button {
-  -webkit-margin-end: auto;
-  -webkit-margin-start: 30px;
+.button-strip {

[James Hawkins, 2012/08/03 22:51:44]

Is this the same button-strip class used in the options code?

[motek., 2012/08/06 18:38:30]

No, it is a coincidence. I needed a container to hold buttons spaced and nicely
aligned. I used to had two buttons here, now there is just one now but I kept
the container since it simplifies attributes. 

+  margin: 1px;
+  text-align: center;
 }
 
-.button-strip {
-  padding: 7px;
+#chrome-logo-box {
+  bottom: 23pt;

[James Hawkins, 2012/08/03 22:51:44]

px

[motek., 2012/08/06 18:38:30]

Done.

+  position: absolute;
+  text-align: center;
+  width: 100%;
 }