Clean up CSS

- Add vim folds to make organized sections
- Rename a lot of classes from post- to page-
- Generalize series CSS classes better
- Clean up navbar div structure
- Remove langpicker and most of multilingual support
- many other minor tweaks

layouts/partials/page-metadata/author.html

@@ -0,0 +1,17 @@
+<div class="page-metadata" aria-label="{{ i18n "aria_author_metadata" }}">
+    {{/* Calculate the total word count */}}
+    {{ $total_words := 0 }}
+    {{ range .Data.Pages }}
+        {{ $total_words = add $total_words .WordCount }}
+    {{ end }}
+
+    <span class="page-metadata-item" aria-label="{{ i18n "aria_author_post_count" }}">
+        {{ partial "icon.html" "newspaper" }}
+        {{ i18n "post_count" (len .Data.Pages) }}
+    </span>
+
+    <span class="page-metadata-item" aria-label="{{ i18n "aria_author_word_count" }}">
+        {{ partial "icon.html" "align-left" }}
+        {{ i18n "wordcount" $total_words }}
+    </span>
+</div>