Add main menu, basic layout

themes/kosmos-22/layouts/partials/topnav.html

@@ -0,0 +1,22 @@
+<header class="max-w-5xl mx-auto px-8 text-left">
+  <div class="flex items-center justify-between h-20">
+    <div class="flex items-center">
+      <div>
+        <h1 class="uppercase font-bold">{{ .Site.Title }}</h1>
+      </div>
+      <nav class="hidden md:block">
+        <ul class="ml-20 flex items-baseline space-x-8">
+          {{ $currentPage := . }}
+          {{ range .Site.Menus.main }}
+          <li class="{{ if $currentPage.IsMenuCurrent "main" . }}border-b-2 border-teal-500{{ end }}">
+            <a href="{{ .URL }}" class="font-bold">
+              {{ .Pre }}
+              <span>{{ .Name }}</span>
+            </a>
+          </li>
+          {{ end }}
+        </ul>
+      </nav>
+    </div>
+  </div>
+</header>