Use baseurl to refer to resources that might be referred to from subdirs

(such as docs)

Author: hategan

web/_includes/head.html

@@ -1,4 +1,4 @@
-    <link rel="stylesheet" href="/theme-4.css">
+    <link rel="stylesheet" href="{{ site.baseurl }}/theme-4.css">
     <link href="https://fonts.googleapis.com/css2?family=Roboto:wght@100;300;400;500;700;900&family=Open+Sans&family=Saira:wght@300;400&family=Nunito+Sans:wght@300;400" rel="stylesheet">
     <link href="https://cdn.jsdelivr.net/npm/@mdi/[email protected]/css/materialdesignicons.min.css" rel="stylesheet">
     <link href="https://cdn.jsdelivr.net/npm/[email protected]/dist/vuetify.min.css" rel="stylesheet">
@@ -12,7 +12,7 @@
     <script src="https://cdnjs.cloudflare.com/ajax/libs/highlight.js/11.4.0/highlight.min.js"></script>
     <link rel="preconnect" href="https://fonts.googleapis.com">
     <link rel="preconnect" href="https://fonts.gstatic.com" crossorigin>
-    <link rel="stylesheet" href="/style.css?id=2">
+    <link rel="stylesheet" href="{{ site.baseurl }}/style.css?id=2">
     <link rel="stylesheet"
         href="https://cdnjs.cloudflare.com/ajax/libs/highlight.js/11.4.0/styles/base16/tender.min.css">
     <script src="https://kit.fontawesome.com/0f2ef02e2b.js" crossorigin="anonymous"></script>