diff --git a/src/_static/css/custom.css b/src/_static/css/custom.css
new file mode 100644
index 00000000..9f53adff
--- /dev/null
+++ b/src/_static/css/custom.css
@@ -0,0 +1,10 @@
+body {
+    /*
+     * These settings are copied from the https://commonwl.org website style
+     * for consistency.
+     */
+    font-family: system-ui, -apple-system, "Segoe UI", Roboto, "Helvetica Neue", Arial, "Noto Sans", "Liberation Sans", sans-serif, "Apple Color Emoji", "Segoe UI Emoji", "Segoe UI Symbol", "Noto Color Emoji";
+    font-size: 16px;
+    line-height: 24px;
+    color: rgb(33, 37, 41);
+}
diff --git a/src/_templates/sidebar-nav-bs.html b/src/_templates/sidebar-nav-bs.html
index 73c66bee..a559969d 100644
--- a/src/_templates/sidebar-nav-bs.html
+++ b/src/_templates/sidebar-nav-bs.html
@@ -1,11 +1,8 @@
 <nav class="bd-links d-none d-md-block" id="bd-docs-nav" aria-label="{{ _('Main navigation') }}">
-  <div class="bd-toc-item active">
-    {{ generate_toctree_html("sidebar",
-                             startdepth=0,
-                             show_nav_level=theme_show_nav_level|int,
-                             maxdepth=theme_navigation_depth|int,
-                             collapse=theme_collapse_navigation|tobool,
-                             includehidden=True,
-                             titles_only=True) }}
+  <p class="bd-links__title" role="heading" aria-level="1">
+    {{ _("Section Navigation") }}
+  </p>
+  <div class="bd-toc-item navbar-nav">
+    {{ sidebar_nav_html }}
   </div>
 </nav>
diff --git a/src/conf.py b/src/conf.py
index c893d8a5..df703367 100644
--- a/src/conf.py
+++ b/src/conf.py
@@ -157,6 +157,10 @@
 # so a file named "default.css" will overwrite the builtin "default.css".
 html_static_path = ['_static']
 
+html_css_files = [
+    'css/custom.css',
+]
+
 html_logo = '_static/images/logos/cwl/CWL-Logo-HD-cropped2.png'
 html_favicon = '_static/images/favicons/cwl/favicon.ico'