improve client UI

app/developer/templates/developer/client_details/advanced.html

@@ -3,6 +3,7 @@
 {% set client_details_page = "advanced" %}
 
 {% block client_details_content %}
+  <h1 class="h2">Danger Zone</h1>
   <form method="post">
     {{ form.csrf_token }}
     <div class="alert alert-danger">When your website is deleted, users can no longer log into it. This operation is not reversible!</div>

app/developer/templates/developer/client_details/basic_info.html

@@ -23,7 +23,7 @@
         action="{{ url_for('developer.client_detail', client_id=client.id, action="edit") }}">
     {{ form.csrf_token }}
 
-    <h3>Info</h3>
+    <h1 class="h2">Info</h1>
     <div class="form-group">
       <label class="form-label">Name</label>
       {{ form.name(class="form-control", value=client.name) }}

app/developer/templates/developer/client_details/oauth_endpoint.html

@@ -3,7 +3,7 @@
 {% set client_details_page = "oauth_endpoint" %}
 
 {% block client_details_content %}
-  <h3>OAuth2 endpoints</h3>
+  <h1 class="h2">OAuth2 endpoints</h1>
 
   <div class="form-group">
     <label class="form-label">OpenID Connect Discovery Document</label>

app/developer/templates/developer/client_details/oauth_setting.html

@@ -5,7 +5,7 @@
 {% block client_details_content %}
   <form method="post">
     {{ form.csrf_token }}
-    <h3>OAuth2 Settings</h3>
+    <h1 class="h2">OAuth2 Settings</h1>
 
     <div class="form-group">
       <label class="form-label">AppID / OAuth2 Client ID</label>