Mention CSS files in static assets overview

Closes #1892

docs/content/documentation/content/overview.md

@@ -85,7 +85,7 @@ In addition to placing content files in the `content` directory, you may also pl
 files in the `static` directory.  Any files/directories that you place in the `static` directory
 will be copied, without modification, to the `public` directory.
 
-Typically, you might put site-wide assets (such as the site favicon, site logos or site-wide
+Typically, you might put site-wide assets (such as a CSS file, the site favicon, site logos or site-wide
 JavaScript) in the root of the static directory. You can also place any HTML or other files that
 you wish to be included without modification (that is, without being parsed as Markdown files)
 into the static directory.