[css-flexbox] Add advisement styling to author conformance criterium" .

Author: fantasai

css-flexbox/Overview.bs

@@ -1233,6 +1233,8 @@ Reordering and Accessibility</h4>
 	Likewise, 'order' does not affect
 	the default traversal order of sequential navigation modes
 	(such as cycling through links, see e.g. <a href="http://www.w3.org/TR/html5/editing.html#sequential-focus-navigation-and-the-tabindex-attribute"><code>tabindex</code></a> [[HTML5]]).
+
+	Advisement:
 	Authors <em>must</em> use 'order' only for visual, not logical, reordering of content;
 	style sheets that use 'order' to perform logical reordering are non-conforming.
 

css-flexbox/Overview.html

@@ -1294,9 +1294,9 @@ <h4 class="heading settled" data-level="5.4.1" id="order-accessibility"><span cl
 	(such as <a href="http://www.w3.org/TR/css3-speech/">speech</a>).
 	Likewise, <a class="property" data-link-type="propdesc" href="#propdef-order">order</a> does not affect
 	the default traversal order of sequential navigation modes
-	(such as cycling through links, see e.g. <a href="http://www.w3.org/TR/html5/editing.html#sequential-focus-navigation-and-the-tabindex-attribute"><code>tabindex</code></a><a data-link-type="biblio" href="#biblio-html5">[HTML5]</a>).
-	Authors <em>must</em> use <a class="property" data-link-type="propdesc" href="#propdef-order">order</a> only for visual, not logical, reordering of content;
-	style sheets that use <a class="property" data-link-type="propdesc" href="#propdef-order">order</a> to perform logical reordering are non-conforming.</p>
+	(such as cycling through links, see e.g. <a href="http://www.w3.org/TR/html5/editing.html#sequential-focus-navigation-and-the-tabindex-attribute"><code>tabindex</code></a><a data-link-type="biblio" href="#biblio-html5">[HTML5]</a>).</p>
+   <strong class="advisement"> Authors <em>must</em> use <a class="property" data-link-type="propdesc" href="#propdef-order">order</a> only for visual, not logical, reordering of content;
+	style sheets that use <a class="property" data-link-type="propdesc" href="#propdef-order">order</a> to perform logical reordering are non-conforming.</strong>
    <p class="note" role="note">Note: This is so that non-visual media and non-CSS UAs,
 	which typically present content linearly,
 	can rely on a logical source order,