add subtitles to blog list and tag list

_layouts/tag.html

@@ -20,11 +20,16 @@ layout: default
       <header class="post-title">
         <h1>
           <a href="{{site.base-url}}{{ post.url }}#main">{{ post.title }}</a>
+        </h1>
         <time datetime="{{ post.date | date_to_xmlschema }}" class="post-date">
           {{ post.date | date: "%B %e, %Y" }}
         </time>
+        {% if post.subtitle %}
+        <h2>
+          {{ post.subtitle }}
+        </h2>
+        {% endif %}
         {% if post.tags.size > 0 %}
-          </h1>
           <ol class="tags-list">
             {% for post_tag in post.tags %}
               {% assign tag = site.data.tags[post_tag] %}

blog/index.html

@@ -9,11 +9,16 @@ layout: default
 	<header class="post-title">
 		<h1>
 			<a href="{{site.base-url}}{{ post.url }}#main">{{ post.title }}</a>
+		</h1>
 		<time datetime="{{ post.date | date_to_xmlschema }}" class="post-date">
 			{{ post.date | date: "%B %e, %Y" }}
 		</time>
+		{% if post.subtitle %}
+		<h2>
+			{{ post.subtitle }}
+		</h2>
+		{% endif %}
 		{% if post.tags.size > 0 %}
-		</h1>
 		<ol class="tags-list">
 			{% for post_tag in post.tags %}
 				{% assign tag = site.data.tags[post_tag] %}

css/posts.scss

@@ -218,6 +218,7 @@ header>h1>a:link, header>h1>a:visited {
 	.post-title>h2 {
 		flex-basis: 50%;
 		margin: auto 0;
+		font-size: 1.3em;
 	}
 
 	.post-title>ol.tags-list {