[css-pseudo] Fix copy-paste error in ::after, thanks to shepazu

Author: fantasai

css-pseudo/Overview.bs

@@ -629,7 +629,7 @@ Generated Content Pseudo-elements: ''::before'' and ''::after''</h3>
 
     <dt><dfn>::after</dfn>
     <dd>Represents a styleable child pseudo-element
-    immediately before the <i>originating element</i>'s actual content.
+    immediately after the <i>originating element</i>'s actual content.
   </dl>
 
   <div class="example">

css-pseudo/Overview.html

@@ -1020,7 +1020,7 @@ <h3 class="heading settled" data-level="4.1" id="generated-content"><span class=
     <dt><dfn class="css" data-dfn-type="selector" data-export="" id="selectordef-after">::after<a class="self-link" href="#selectordef-after"></a></dfn>
 
     <dd>Represents a styleable child pseudo-element
-    immediately before the <i>originating element</i>’s actual content.
+    immediately after the <i>originating element</i>’s actual content.
 
    </dl>