drop <main>, use <article role="main"> — bold landmark structure

body direct children: <nav>, <header>, <article role="main">, <footer>
- <nav>: site navigation (own landmark)
- <header>: page identity — title, author, date, metadata
- <article role="main">: content (screen reader gets landmark via role)
- <footer>: site footer

No <main> wrapper. Fewer tags, clearer signal.
Header block defined per-layout (prose gets eyebrow/date, docs gets hgroup).
Content block defined per-layout (docs adds sidebar <nav> + <aside> TOC).

layouts/_default/single.html

@@ -1,25 +1,24 @@
-{{ define "main" }}
-  <main>
-    <article data-layout="prose">
-
-      <header>
-        <hgroup>
-          {{ with .Params.eyebrow }}<p data-text="eyebrow">{{ . }}</p>{{ end }}
-          <h1>{{ .Title }}</h1>
-          {{ with .Description }}<p>{{ . }}</p>{{ end }}
-        </hgroup>
-        <p data-text="dim">
-          <time datetime="{{ .Date.Format `2006-01-02` }}">{{ .Date.Format "January 2006" }}</time>
-          {{ with .Params.author }} · {{ . }}{{ end }}
-        </p>
-      </header>
-
-      {{ .Content }}
-
-      <footer>
-        <small>{{ with .Params.footer }}{{ . }}{{ else }}Published in the dorveille.{{ end }}</small>
-      </footer>
-
-    </article>
-  </main>
+{{ define "header" }}
+  <header>
+    <hgroup>
+      {{ with .Params.eyebrow }}<p data-text="eyebrow">{{ . }}</p>{{ end }}
+      <h1>{{ .Title }}</h1>
+      {{ with .Description }}<p>{{ . }}</p>{{ end }}
+    </hgroup>
+    <p data-text="dim">
+      <time datetime="{{ .Date.Format "2006-01-02" }}">{{ .Date.Format "January 2006" }}</time>
+      {{ with .Params.author }} · {{ . }}{{ end }}
+    </p>
+  </header>
+{{ end }}
+
+{{ define "content" }}
+  <article role="main">
+    {{ .Content }}
+    {{ with .Params.footer }}
+    <footer>
+      <small>{{ . }}</small>
+    </footer>
+    {{ end }}
+  </article>
 {{ end }}