Issue 5676 - Relax CSS coding style

pages/coding-style.html

Index: pages/coding-style.html
===================================================================
--- a/pages/coding-style.html
+++ b/pages/coding-style.html
@@ -45,18 +45,18 @@
 <h2 id="html-css">{{html-css HTML and CSS}}</h2>
 <ul>
   <li>{{html-css-general Follow the <a href="https://google.github.io/styleguide/htmlcssguide.html">Google HTML/CSS Style Guide</a>.}}</li>
   <li>{{html-css-quotation Use double over single quotation marks.}}</li>
   <li>{{html-css-optional-tag Don't omit optional HTML tags.}}</li>
   <li>{{html-css-hexadecimal CSS color values should be specified in hexadecimal where possible.}}</li>
   <li>{{html-css-shorthand CSS shorthand properties usage is optional.}}</li>
   <li>{{html-css-order CSS rule declaration order should follow the <a href="https://make.wordpress.org/core/handbook/best-practices/coding-standards/css/#property-ordering">WordPress CSS Coding Standards</a>.}}</li>
-  <li>{{html-css-units CSS number values should specify units where possible.}}</li>
   <li>{{html-css-leading-zero Don't omit the optional leading 0 for decimal numbers.}}</li>
+  <li>{{html-css-single-line CSS declaration blocks with a single selector and a single rule can be written in a single line.}}</li>
 </ul>
 
 <h2 id="python">{{s19 Python}}</h2>
 <ul>
   <li>{{python-general Follow <a href="https://www.python.org/dev/peps/pep-0008/"><fix>PEP-8</fix></a> and the recommendations in the offical <fix>Python</fix> documentation.}}</li>
   <li>{{python-version Make the code compatible with both <fix>Python 2.7</fix> and <fix>Python 3.5+</fix> (see <a href="https://docs.python.org/dev/howto/pyporting.html">this guide</a>). Use <a href="https://docs.python.org/2/library/__future__.html"><fix>__future__</fix> imports</a> to address syntactic differences but avoid <a href="https://pythonhosted.org/six/"><fix>six</fix></a>, <a href="http://python-future.org/compatible_idioms.html"><fix>python-future</fix></a>, etc. to not introduce additional dependencies.}}</li>
   <li>{{python-strings Write string literals so that they match the behaviour of <a href="https://docs.python.org/3/library/functions.html#ascii"><code><fix>ascii()</fix></code></a>, i.e. use single quotes except to avoid escaping of embedded quotes and use <code><fix>\u</fix></code> escapes for non-ascii characters but don't prefix strings with <code><fix>u</fix></code>. For docstrings, however, follow <a href="https://www.python.org/dev/peps/pep-0257/">PEP-257</a>.}}</li>
   <li>{{python-prefix In modules, prefix private functions and variables with a single underscore.}}</li>