Respect base URL for nav logo; prefer logo.svg over favicon.svg

Reference the navbar brand image through relURL so it resolves
correctly when the site is served from a non-root base URL. Use
static/img/logo.svg when present, falling back to img/favicon.svg.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

README.md

@@ -1,3 +1,15 @@
 # hugo_bootstrap_theme
 
 Simple Bootstrap-based theme for Hugo.
+
+
+## Custom error page
+
+The theme has a custom 404 error page.
+
+If the site has an SVG image in `assets/svg/404.svg`,
+this image will be displayed instead of a generic 404
+code. Regardless of whether an SVG assets exists or not,
+English and German explanations of what's going on will
+be included on the page.
+

layouts/404.html

@@ -1,11 +1,19 @@
 {{ define "main" }}
 <div class="container">
   <div class="row">
-    <div class="col">
+    <div class="col mt-5 mb-5">
+      {{ with resources.Get "svg/404.svg" }}
+        {{ .Content | safeHTML }}
+      {{ else }}
         <h1 class="display-1 mx-auto text-center">
           404
         </h1>
-      <div class="alert alert-danger mb-5">
+      {{ end }}
+    </div>
+  </div>
+  <div class="row">
+    <div class="col-lg-6">
+      <div class="alert alert-danger mb-5" lang="en">
         <h4 class="alert-heading">
           Page not found
         </h4>
@@ -18,7 +26,9 @@
           <a href="{{ .Site.BaseURL }}" class="alert-link">Back to the home page.</a>
         </p>
       </div>
-      <div class="alert alert-warning">
+    </div>
+    <div class="col-lg-6">
+      <div class="alert alert-danger" lang="de">
         <h4 class="alert-heading">
           Seite nicht gefunden
         </h4>

layouts/_partials/footer.html

@@ -2,7 +2,7 @@
   <div class="container py-4">
     <div class="row">
       <div class="col-md-6">
-        <p>&copy; {{ now.Year }} {{ .Site.Title }}</p>
+        <p>&copy; {{ now.Year }} {{ or (or .Params.Author .Site.Params.Author) .Site.Title }}</p>
       </div>
       <div class="col-md-6 text-md-end">
         <p>

layouts/_partials/header.html

@@ -1,7 +1,9 @@
 <nav class="navbar navbar-expand-lg navbar-light bg-light sticky-top">
   <div class="container"> <!-- Changed from container-fluid to container -->
     <a class="navbar-brand fw-bold" href="{{ .Site.BaseURL }}">
-      <img src="/img/favicon.svg" alt="{{ .Site.Title }}" title="{{ .Site.Title }}">
+      {{- $logo := "img/favicon.svg" -}}
+      {{- if os.FileExists "static/img/logo.svg" -}}{{- $logo = "img/logo.svg" -}}{{- end -}}
+      <img src="{{ $logo | relURL }}" alt="{{ .Site.Title }}" title="{{ .Site.Title }}">
     </a>
     
     <button class="navbar-toggler" type="button" data-bs-toggle="collapse" 

layouts/_partials/scripts_extra.html

@@ -0,0 +1,2 @@
+<!-- extra scripts may go here -->
+