Revert "Switch to gruvbox theme"

This reverts commit 66cff08323.

themes/archie/layouts/partials/head.html

@@ -0,0 +1,23 @@
+<header>
+  <div class="main">
+    <a href="{{ .Site.BaseURL }}">{{ .Site.Title }}</a>
+  </div>
+  <nav>
+    {{ range .Site.Menus.main }}
+    <a href="{{ .URL }}">{{ .Name }}</a>
+    {{ end }} {{ if eq .Site.Params.mode "toggle" -}}
+  </nav>
+  <script
+    type="text/javascript"
+    src="https://storage.ko-fi.com/cdn/widget/Widget_2.js"
+  ></script>
+  <span id="dark-mode-toggle" onclick="toggleTheme()"></span>
+  <script src="{{ .Site.BaseURL }}js/themetoggle.js"></script>
+  {{ end }}
+  {{ if (findRE "<pre" .Content 1) }}
+
+    {{ $copyCss := resources.Get "css/copy-code-button.css" | minify }}
+    <link href="{{ $copyCss.RelPermalink }}" rel="stylesheet">
+{{ end }}
+
+</header>