[docs](doc): Expires(in future)

Signed-off-by: Ralph Hightower <[email protected]>

Author: RalphHightower

_includes/custom-head.html

@@ -3,13 +3,17 @@
 
   1. Head over to https://realfavicongenerator.net/ to add your own favicons.
   2. Customize default _includes/custom-head.html in your source directory and insert the given code snippet.
+Expires: Thu, 01 Dec 1994 16:00:00 GMT
+%a, %d %b %Y %T %Z
 {% endcomment %}
 
-<link rel="preload" href="Mona-Sans.woff2" as="font" type="font/woff2" crossorigin>
-<link rel="preload" href="Hubot-Sans.woff2" as="font" type="font/woff2" crossorigin>
+{% expire = 'now' | date: '%s' | plus: 60 | date: '%a, %d %b %Y %T %Z' %}
 
 {% if page.url contains "WhereIsTrump-Countdown" %}
 <meta http-equiv="Cache-Control" content="no-cache, no-store, max-age=1, must-revalidate">
 <meta http-equiv="Pragma" content="no-cache">
-<meta http-equiv="Expires" content="1">
+<meta http-equiv="Expires" content="expires">
 {% endif %}
+
+<link rel="preload" href="Mona-Sans.woff2" as="font" type="font/woff2" crossorigin>
+<link rel="preload" href="Hubot-Sans.woff2" as="font" type="font/woff2" crossorigin>