Increase admonition.important contrast

Lighten the background and darken the text colors in the
admonition.important box to make it easier to read the (important!)
text within.

Change-Id: Idb449c02a0a0832b5f379e53c373cc4dd1fe0e81

doc/source/demo/index.rst

@@ -82,7 +82,22 @@ Here's the same example but with ..code-block: ini to test the pygments lexer:
   vncserver_proxyclient_address = 10.0.0.31
   novncproxy_base_url = http://controller:6080/vnc_auto.html
 
-.. note:: Here's an example note.
+Notices
+~~~~~~~
+
+Notices take these forms:
+
+.. note:: A comment with additional information that explains a part of the
+          text.
+
+.. important:: Something you must be aware of before proceeding.
+
+.. tip:: An extra but helpful piece of practical advice.
+
+.. caution:: Helpful information that prevents the user from making mistakes.
+
+.. warning:: Critical information about the risk of data loss or security
+             issues.
 
 .. toctree::
     :maxdepth: 1

openstackdocstheme/theme/openstackdocs/static/css/combined.css

@@ -4183,18 +4183,18 @@ pre .cl {
    originally had names "docs-important" and "docs-warning" */
 
 .admonition.important {
-  background: #FEFFBE;
-  border-color: #D7AA16;
-  color: #D7AA16; }
+  background: #feffd6;
+  border-color: #2A4E68;
+  color: #2A4E68; }
 
 .admonition.important a {
-  color: #e8be15; }
+  color: #cca50a; }
 
 .admonition.important h3 {
-  color: #e8be15; }
+  color: #cca50a; }
 
 .admonition.important h3 i {
-  color: #e8be15; }
+  color: #cca50a; }
 
 .admonition.warning {
   background: #FED3D9;