[css-pseudo] Fix copy-paste error.

Author: fantasai

css-pseudo/Overview.bs

@@ -665,7 +665,7 @@ List Markers: the ''::marker'' pseudo-element</h3>
   the automatically generated marker box of a list item.
   (See ''display: list-item''.)
 
-  The following CSS properties apply to a ''::first-line'' pseudo-element:
+  The following CSS properties apply to a ''::marker'' pseudo-element:
   <ul>
     <li>all font properties (see [[CSS3-FONTS]])
     <li>the 'color' property (see [[CSS3COLOR]])