A11y: dark mode contrast, sign-in landmark/h1, Banner link discernibility

lib/mv_web/auth_overrides.ex

@@ -32,10 +32,11 @@ defmodule MvWeb.AuthOverrides do
     set :root_class, "md:min-w-md"
   end
 
-  # Replace banner logo with text
+  # Replace banner logo with text (no image in light or dark so link has discernible text)
   override AshAuthentication.Phoenix.Components.Banner do
     set :text, "Mitgliederverwaltung"
     set :image_url, nil
+    set :dark_image_url, nil
   end
 
   # Translate the "or" in the horizontal rule (between password form and SSO).

lib/mv_web/live/auth/sign_in_live.ex

@@ -54,13 +54,15 @@ defmodule MvWeb.SignInLive do
   @impl true
   def render(assigns) do
     ~H"""
-    <div
+    <main
       id="sign-in-page"
+      role="main"
       class={@root_class}
       data-oidc-configured={to_string(@oidc_configured)}
       data-oidc-only={to_string(@oidc_only)}
       data-locale={@locale}
     >
+      <h1 class="sr-only">{dgettext("auth", "Sign in")}</h1>
       <%!-- Language selector --%>
       <nav
         aria-label={dgettext("auth", "Language selection")}
@@ -95,7 +97,7 @@ defmodule MvWeb.SignInLive do
         context={@context}
         gettext_fn={@gettext_fn}
       />
-    </div>
+    </main>
     """
   end
 end