diff --git a/lib/towerops_web/components/layouts.ex b/lib/towerops_web/components/layouts.ex
index 7fd586b7..d878590a 100644
--- a/lib/towerops_web/components/layouts.ex
+++ b/lib/towerops_web/components/layouts.ex
@@ -606,7 +606,7 @@ defmodule ToweropsWeb.Layouts do
       </div>
 
       <!-- Main content -->
-      <div id="main-wrapper">
+      <div id="main-wrapper" class="flex flex-col min-h-[calc(100vh-3.5rem)]">
         <main id="main-content" tabindex="-1" class="flex-1 py-6 sm:py-10 page-fade-in">
           <div class="mx-auto max-w-7xl px-4 sm:px-6 lg:px-8">
             <!-- Beta Testing Banner -->
diff --git a/test/towerops_web/components/layouts_test.exs b/test/towerops_web/components/layouts_test.exs
new file mode 100644
index 00000000..b84b9139
--- /dev/null
+++ b/test/towerops_web/components/layouts_test.exs
@@ -0,0 +1,167 @@
+defmodule ToweropsWeb.LayoutsTest do
+  use ToweropsWeb.ConnCase
+
+  import Phoenix.LiveViewTest
+
+  setup :register_and_log_in_user
+
+  setup %{conn: conn, user: user} do
+    {:ok, organization} =
+      Towerops.Organizations.create_organization(
+        %{name: "Test Org", use_sites: true},
+        user.id
+      )
+
+    conn = Plug.Conn.put_session(conn, :current_organization_id, organization.id)
+
+    %{conn: conn, organization: organization}
+  end
+
+  describe "authenticated layout - sidebar navigation" do
+    test "renders sidebar with grouped navigation sections", %{conn: conn} do
+      {:ok, _view, html} = live(conn, ~p"/dashboard")
+
+      # Sidebar container
+      assert html =~ ~s(id="app-sidebar")
+      assert html =~ ~s(id="sidebar-wrapper")
+
+      # Section headers
+      assert html =~ "Monitor"
+      assert html =~ "Respond"
+      assert html =~ "Analyze"
+
+      # Monitor section links
+      assert html =~ ~s(href="/dashboard")
+      assert html =~ ~s(href="/devices")
+      assert html =~ ~s(href="/sites")
+      assert html =~ ~s(href="/network-map")
+
+      # Respond section links
+      assert html =~ ~s(href="/alerts")
+      assert html =~ ~s(href="/maintenance")
+      assert html =~ ~s(href="/schedules")
+
+      # Analyze section links
+      assert html =~ ~s(href="/insights")
+      assert html =~ ~s(href="/trace")
+      assert html =~ ~s(href="/activity")
+    end
+
+    test "renders slim top bar with search, alerts, help, and user menu", %{conn: conn} do
+      {:ok, _view, html} = live(conn, ~p"/dashboard")
+
+      # Logo in top bar
+      assert html =~ "Towerops"
+
+      # Search trigger
+      assert html =~ ~s(id="global-search-trigger")
+      assert html =~ "⌘K"
+
+      # Alert bell
+      assert html =~ ~s(hero-bell)
+
+      # Help icon
+      assert html =~ ~s(href="/help")
+
+      # User menu button
+      assert html =~ ~s(id="org-menu-button")
+    end
+
+    test "renders sidebar collapse toggle", %{conn: conn} do
+      {:ok, _view, html} = live(conn, ~p"/dashboard")
+
+      assert html =~ ~s(data-sidebar-toggle)
+      assert html =~ "hero-chevron-double-left"
+    end
+
+    test "highlights active page in sidebar", %{conn: conn} do
+      {:ok, _view, html} = live(conn, ~p"/dashboard")
+
+      # Dashboard link should have active styling
+      assert html =~ ~r/bg-blue-50.*href="\/dashboard"/s
+    end
+
+    test "renders org switcher in sidebar bottom", %{conn: conn} do
+      {:ok, _view, html} = live(conn, ~p"/dashboard")
+
+      assert html =~ ~s(id="sidebar-org-switcher-button")
+      assert html =~ "Test Org"
+      assert html =~ "Switch Organization"
+      assert html =~ "Organization Settings"
+    end
+
+    test "renders settings link in sidebar", %{conn: conn, organization: org} do
+      {:ok, _view, html} = live(conn, ~p"/dashboard")
+
+      assert html =~ ~s(href="/orgs/#{org.slug}/settings")
+    end
+
+    test "hides sites link when use_sites is false", %{conn: conn, organization: org} do
+      # Disable sites on the existing org
+      Towerops.Organizations.update_organization(org, %{use_sites: false})
+
+      {:ok, _view, html} = live(conn, ~p"/dashboard")
+
+      # Sites should NOT appear as a sidebar nav link
+      refute html =~ ~s(href="/sites")
+    end
+
+    test "no horizontal More dropdown exists", %{conn: conn} do
+      {:ok, _view, html} = live(conn, ~p"/dashboard")
+
+      refute html =~ ~s(id="more-nav-button")
+      refute html =~ ~s(id="more-nav-menu")
+    end
+  end
+
+  describe "authenticated layout - mobile menu" do
+    test "renders mobile menu with grouped sections", %{conn: conn} do
+      {:ok, _view, html} = live(conn, ~p"/dashboard")
+
+      assert html =~ ~s(id="mobile-menu")
+      assert html =~ ~s(id="mobile-menu-button")
+
+      # Mobile menu contains all nav sections
+      # (Mobile menu has same links as sidebar)
+      assert html =~ "hero-home"
+      assert html =~ "hero-server"
+      assert html =~ "hero-bell-alert"
+      assert html =~ "hero-wrench-screwdriver"
+      assert html =~ "hero-light-bulb"
+      assert html =~ "hero-clock"
+    end
+  end
+
+  describe "authenticated layout - user menu" do
+    test "renders user menu items", %{conn: conn} do
+      {:ok, _view, html} = live(conn, ~p"/dashboard")
+
+      assert html =~ ~s(id="org-menu")
+      assert html =~ "User Settings"
+      assert html =~ "My Data"
+      assert html =~ "What&#39;s New"
+      assert html =~ "Log out"
+    end
+  end
+
+  describe "authenticated layout - beta banner" do
+    test "renders beta testing banner", %{conn: conn} do
+      {:ok, _view, html} = live(conn, ~p"/dashboard")
+
+      assert html =~ ~s(id="beta-banner")
+      assert html =~ "Thanks for testing Towerops!"
+      assert html =~ "hi@towerops.net"
+    end
+  end
+
+  describe "authenticated layout - footer" do
+    test "renders footer with copyright and links", %{conn: conn} do
+      {:ok, _view, html} = live(conn, ~p"/dashboard")
+
+      assert html =~ "Copyright"
+      assert html =~ "Towerops"
+      assert html =~ "Privacy Policy"
+      assert html =~ "Terms of Service"
+    end
+  end
+end