refactor: add .section-title (#36)

For the small title before the card

Remove .widget-title, .archive-date, .taxonomy-type from SCSS, as they all share the same style.

layouts/partials/article/components/related-contents.html

@@ -1,7 +1,7 @@
-<aside class="widget related-contents--wrapper">
+<aside class="related-contents--wrapper">
     {{ $related := .Site.RegularPages.Related . | first 5 }}
     {{ with $related }}
-        <h1 class="widget-title">{{ T "relatedContents" }}</h1>
+        <h2 class="section-title">{{ T "relatedContents" }}</h2>
         <div class="related-contents">
             <div class="flex article-list--tile">
                 {{ range . }}

layouts/partials/widget/archives.html

@@ -2,7 +2,7 @@
     <div class="widget-icon">
         {{ partial "helper/icon" "infinity" }}
     </div>
-    <h1 class="widget-title">{{ T "widgetArchivesTitle" }}</h1>
+    <h2 class="widget-title section-title">{{ T "widgetArchivesTitle" }}</h2>
 
     {{ $pages := where .Site.RegularPages "Type" "in" .Site.Params.mainSections }}
     {{ $notHidden := where .Site.RegularPages "Params.hidden" "!=" true }}

layouts/partials/widget/tag-cloud.html

@@ -2,7 +2,7 @@
     <div class="widget-icon">
         {{ partial "helper/icon" "tag" }}
     </div>
-    <h1 class="widget-title">{{ T "widgetTagCloudTitle" }}</h1>
+    <h2 class="widget-title section-title">{{ T "widgetTagCloudTitle" }}</h2>
 
     <div class="tagCloud-tags">
         {{ range first .Site.Params.widgets.tagCloud.limit .Site.Taxonomies.tags.ByCount }}