diff --git a/css/base.css b/css/base.css
index 9817cb34..ced7d968 100644
--- a/css/base.css
+++ b/css/base.css
@@ -31,18 +31,19 @@
   }
   h1 {
     font-size: var(--font-size-6);
+    font-weight: normal;
   }
   h2 {
-    font-size: var(--font-size-5);
+    font-size: var(--font-size-4);
   }
   h3 {
-    font-size: var(--font-size-4);
+    font-size: var(--font-size-3);
   }
   h4 {
-    font-size: var(--font-size-3);
+    font-size: var(--font-size-2);
   }
   h5 {
-    font-size: var(--font-size-2);
+    font-size: var(--font-size-1);
   }
   h6 {
     font-size: var(--font-size-1);
diff --git a/css/components/menu.css b/css/components/menu.css
index 0f2556e4..b93622ee 100644
--- a/css/components/menu.css
+++ b/css/components/menu.css
@@ -1,38 +1,86 @@
 @layer components {
-
-/**
+  /**
  * @file
  * Visual styles for menu.
  */
 
-ul.menu {
-  margin-left: 1em; /* LTR */
-  padding: 0;
-  list-style: none outside;
-  text-align: left; /* LTR */
-}
-[dir="rtl"] ul.menu {
-  margin-right: 1em;
-  margin-left: 0;
-  text-align: right;
-}
-.menu-item--expanded {
-  list-style-type: circle;
-  list-style-image: url(../../images/icons/menu-expanded.png);
-}
-.menu-item--collapsed {
-  list-style-type: disc;
-  list-style-image: url(../../images/icons/menu-collapsed.png); /* LTR */
-}
-[dir="rtl"] .menu-item--collapsed {
-  list-style-image: url(../../images/icons/menu-collapsed-rtl.png);
-}
-.menu-item {
-  margin: 0;
-  padding-top: 0.2em;
-}
-ul.menu a.is-active {
-  color: #000;
-}
+  ul.menu {
+    margin-left: 1em; /* LTR */
+    padding: 0;
+    list-style: none outside;
+    text-align: left; /* LTR */
+  }
+  [dir="rtl"] ul.menu {
+    margin-right: 1em;
+    margin-left: 0;
+    text-align: right;
+  }
+  .menu-item--expanded {
+    list-style-type: circle;
+    list-style-image: url(../../images/icons/menu-expanded.png);
+  }
+  .menu-item--collapsed {
+    list-style-type: disc;
+    list-style-image: url(../../images/icons/menu-collapsed.png); /* LTR */
+  }
+  [dir="rtl"] .menu-item--collapsed {
+    list-style-image: url(../../images/icons/menu-collapsed-rtl.png);
+  }
+  .menu-item {
+    margin: 0;
+    padding-top: 0.2em;
+  }
+  ul.menu a.is-active {
+    color: #000;
+  }
+  /* dropdown behaviours */
+
+  /* add the region with a menu in it to convert to a dropdown */
+  /* check the menu js behaviour when adding new dropdowns */
+  header {
+    .menu {
+      display: flex;
+    }
+    .menu ul {
+      list-style: none;
+      margin: 0;
+      padding: 0;
+    }
+
+    .menu > ul {
+      display: flex;
+      gap: 1rem;
+    }
+
+    .menu li {
+      position: relative;
+    }
+
+    /* Hide submenus */
+    .menu li ul {
+      position: absolute;
+      top: 100%;
+      left: 0;
+      display: none;
+      min-width: 200px;
+      background: white;
+      box-shadow: 0 4px 10px rgba(0, 0, 0, 0.1);
+    }
+
+    /* Show submenu on hover */
+    .menu li:hover > ul {
+      display: block;
+    }
+
+    /* Optional styling */
+    .menu a {
+      display: block;
+      padding: 0.75rem 1rem;
+      text-decoration: none;
+    }
 
+    .menu li ul li a {
+      padding: 0.5rem 1rem;
+    }
+  }
 }
diff --git a/css/components/unsorted.css b/css/components/unsorted.css
new file mode 100644
index 00000000..b0208bec
--- /dev/null
+++ b/css/components/unsorted.css
@@ -0,0 +1,122 @@
+@layer components {
+  /* ======================================= */
+  /* sidebar menu styles */
+  /* ======================================= */
+
+  /* sliding yellow links, no dropdowns */
+  .null.region-sidebar-second {
+    .menu {
+      margin: 0;
+    }
+    .menu a {
+      text-decoration: none;
+      display: block;
+      background-image: url(data:image/png;base64,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);
+      background-position: 96% 10px;
+      background-repeat: no-repeat;
+      padding: 6px 20px 6px 0;
+      background-color: transparent;
+      color: #192a36;
+      /* display: inline-block; */
+      /* padding: 0 3px; */
+      margin-left: 0;
+      margin-right: -3px;
+      position: relative;
+      text-decoration: none;
+      transition: color ease 0.3s;
+      z-index: 0;
+    }
+    li.menu-item {
+      border-bottom: 2px solid var(--upei-orange);
+      font-size: 16px;
+      padding-top: 0;
+      a:before {
+        content: "";
+        position: absolute;
+        z-index: -1;
+        width: 0;
+        height: 100%;
+        left: 0;
+        bottom: 0;
+        background-color: var(--upei-orange);
+        transition: all ease 0.3s;
+      }
+      a:hover:before {
+        width: 100%;
+      }
+    }
+  }
+  /* sidebar block menu with dropdowns (may need to adjust .block-menu and/or regions) */
+  /* *see the associated behavior */
+  .region-sidebar-second {
+    nav h2 {
+      margin-bottom: 0;
+    }
+    nav ul.menu li a {
+      text-decoration: none;
+      padding: 7px 0 7px 10px;
+      display: block;
+      border-bottom: 2px solid #8c2004;
+      color: #192a36;
+    }
+    .menu {
+      margin: 0;
+      /* margin-bottom: 1rem; */
+    }
+    .menu-item {
+      padding: 0;
+    }
+    .menu-item--expanded .menu a {
+      margin-left: 1em;
+      border: none;
+    }
+    /* Hide nested menus by default */
+    .block-menu .menu-item--expanded > ul {
+      display: none;
+    }
+
+    /* Show when open */
+    .block-menu .menu-item--expanded.open > ul {
+      display: block;
+    }
+
+    /* Position container */
+    .block-menu .menu-item--expanded {
+      position: relative;
+      list-style-type: none;
+      list-style-image: none;
+    }
+
+    /* Caret button */
+    .block-menu .menu-caret {
+      position: absolute;
+      right: 0.5rem;
+      top: 0.75rem;
+      cursor: pointer;
+      font-size: 0.8rem;
+      user-select: none;
+    }
+
+    /* Optional caret icon (triangle) */
+    .block-menu .menu-caret::after {
+      content: "▼";
+    }
+
+    /* Rotate when open */
+    .block-menu .menu-item--expanded.open > .menu-caret::after {
+      transform: rotate(180deg);
+      display: inline-block;
+    }
+
+    .block-menu .menu-item--expanded > ul {
+      display: block;
+      max-height: 0;
+      overflow: hidden;
+      transition: max-height 0.5s ease;
+    }
+
+    .block-menu .menu-item--expanded.open > ul {
+      max-height: 500px;
+    }
+  }
+}
diff --git a/css/layout.css b/css/layout.css
index 6b183d2b..64164439 100644
--- a/css/layout.css
+++ b/css/layout.css
@@ -18,7 +18,6 @@
  * responsiveness — see todo.md for the rationale.
  */
 @layer layout {
-
   .content-rail {
     max-width: var(--content-max-width);
     margin-inline: auto;
@@ -36,6 +35,7 @@
     padding-block: var(--size-3);
   }
 
+  .region-header,
   .top-nav__inner {
     display: flex;
     justify-content: space-between;
@@ -65,7 +65,9 @@
      No-sidebar pages skip the grid entirely; .layout-content just fills
      its parent rail. */
 
-  body:is(.layout-sidebar-first, .layout-sidebar-second, .layout-two-sidebars) main > .content-rail {
+  body:is(.layout-sidebar-first, .layout-sidebar-second, .layout-two-sidebars)
+    main
+    > .content-rail {
     display: grid;
     gap: var(--size-4);
     grid-template-columns: minmax(0, 1fr);
@@ -81,9 +83,15 @@
     grid-template-areas: "content" "first" "second";
   }
 
-  .layout-content        { grid-area: content; }
-  .layout-sidebar-first  { grid-area: first; }
-  .layout-sidebar-second { grid-area: second; }
+  .layout-content {
+    grid-area: content;
+  }
+  .layout-sidebar-first {
+    grid-area: first;
+  }
+  .layout-sidebar-second {
+    grid-area: second;
+  }
 
   /* Tablet+: single-sidebar layouts side-by-side. */
   @media (min-width: 768px) {
@@ -100,9 +108,10 @@
   /* Small-desktop+: two-sidebar layout becomes three columns. */
   @media (min-width: 1024px) {
     body.layout-two-sidebars main > .content-rail {
-      grid-template-columns: var(--sidebar-width) minmax(0, 1fr) var(--sidebar-width);
+      grid-template-columns: var(--sidebar-width) minmax(0, 1fr) var(
+          --sidebar-width
+        );
       grid-template-areas: "first content second";
     }
   }
-
 }
diff --git a/druid.libraries.yml b/druid.libraries.yml
index b43df62a..32de0faa 100644
--- a/druid.libraries.yml
+++ b/druid.libraries.yml
@@ -122,6 +122,8 @@ components:
         weight: -10
       css/components/ui-dialog.css:
         weight: -10
+      css/components/unsorted.css:
+        weight: -10
 dialog:
   version: VERSION
   css:
@@ -144,12 +146,12 @@ image-widget:
   version: VERSION
   css:
     component:
-      css/components/image-widget.css: {  }
+      css/components/image-widget.css: {}
 indented:
   version: VERSION
   css:
     component:
-      css/components/indented.css: {  }
+      css/components/indented.css: {}
 messages:
   version: VERSION
   css:
@@ -184,7 +186,7 @@ search-results:
   version: VERSION
   css:
     component:
-      css/components/search-results.css: {  }
+      css/components/search-results.css: {}
 user:
   version: VERSION
   css:
diff --git a/druid.theme b/druid.theme
index 72398f06..7f5d4647 100644
--- a/druid.theme
+++ b/druid.theme
@@ -15,37 +15,44 @@
  *   - layout-one-sidebar  +  layout-sidebar-second  (only sidebar_second has content)
  *   - layout-two-sidebars
  */
-function druid_preprocess_html(array &$variables): void {
-  $has_first = !empty($variables['page']['sidebar_first']);
-  $has_second = !empty($variables['page']['sidebar_second']);
+function druid_preprocess_html(array &$variables): void
+{
+    $has_first = !empty($variables['page']['sidebar_first']);
+    $has_second = !empty($variables['page']['sidebar_second']);
 
-  if ($has_first && $has_second) {
-    $variables['attributes']['class'][] = 'layout-two-sidebars';
-  }
-  elseif ($has_first) {
-    $variables['attributes']['class'][] = 'layout-one-sidebar';
-    $variables['attributes']['class'][] = 'layout-sidebar-first';
-  }
-  elseif ($has_second) {
-    $variables['attributes']['class'][] = 'layout-one-sidebar';
-    $variables['attributes']['class'][] = 'layout-sidebar-second';
-  }
-  else {
-    $variables['attributes']['class'][] = 'layout-no-sidebars';
-  }
+    if ($has_first && $has_second) {
+        $variables['attributes']['class'][] = 'layout-two-sidebars';
+    } elseif ($has_first) {
+        $variables['attributes']['class'][] = 'layout-one-sidebar';
+        $variables['attributes']['class'][] = 'layout-sidebar-first';
+    } elseif ($has_second) {
+        $variables['attributes']['class'][] = 'layout-one-sidebar';
+        $variables['attributes']['class'][] = 'layout-sidebar-second';
+    } else {
+        $variables['attributes']['class'][] = 'layout-no-sidebars';
+    }
 }
 
 /**
  * Implements hook_preprocess_image_widget().
  */
-function druid_preprocess_image_widget(array &$variables): void {
-  $data = &$variables['data'];
+function druid_preprocess_image_widget(array &$variables): void
+{
+    $data = &$variables['data'];
 
-  // This prevents image widget templates from rendering preview container HTML
-  // to users that do not have permission to access these previews.
-  // @todo revisit in https://drupal.org/node/953034
-  // @todo revisit in https://drupal.org/node/3114318
-  if (isset($data['preview']['#access']) && $data['preview']['#access'] === FALSE) {
-    unset($data['preview']);
-  }
+    // This prevents image widget templates from rendering preview container HTML
+    // to users that do not have permission to access these previews.
+    // @todo revisit in https://drupal.org/node/953034
+    // @todo revisit in https://drupal.org/node/3114318
+    if (isset($data['preview']['#access']) && $data['preview']['#access'] === false) {
+        unset($data['preview']);
+    }
+}
+function druid_preprocess_menu(&$variables)
+{
+    foreach ($variables['items'] as &$item) {
+        if (!empty($item['below'])) {
+            $item['attributes']->addClass('has-dropdown');
+        }
+    }
 }
diff --git a/js/druid.behaviors.js b/js/druid.behaviors.js
index 0cf041c2..07186827 100644
--- a/js/druid.behaviors.js
+++ b/js/druid.behaviors.js
@@ -68,4 +68,90 @@
   //     });
   //   },
   // };
+  Drupal.behaviors.mainMenuToggle = {
+    attach(context) {
+      once(
+        "dropdown-menu-toggle",
+        "nav .menu li.menu-item--expanded > a",
+        context
+      ).forEach((link) => {
+        let touched = false;
+
+        const handler = function (e) {
+          // Prevent duplicate firing (touch + click)
+          if (e.type === "click" && touched) {
+            touched = false;
+            return;
+          }
+
+          if (e.type === "touchstart") {
+            touched = true;
+          }
+
+          const parent = this.parentElement;
+          const submenu = parent.querySelector("ul");
+
+          // Only toggle if submenu exists
+          if (submenu) {
+            e.preventDefault();
+            parent.classList.toggle("open");
+          }
+        };
+
+        // Mobile-first interaction
+        link.addEventListener("touchstart", handler, { passive: true });
+
+        // Desktop + accessibility fallback
+        link.addEventListener("click", handler);
+      });
+    },
+  };
+})(Drupal, once);
+((Drupal, once) => {
+  Drupal.behaviors.sidebarMenuDropdown = {
+    attach(context) {
+      once(
+        "sidebar-menu-dropdown",
+        ".block-menu .menu-item--expanded",
+        context
+      ).forEach((item) => {
+        const link = item.querySelector("a");
+        const submenu = item.querySelector("ul");
+
+        if (!submenu || !link) return;
+
+        // ✅ Create caret element
+        const caret = document.createElement("span");
+        caret.className = "menu-caret";
+        caret.setAttribute("aria-expanded", "false");
+
+        // Insert caret after link
+        link.insertAdjacentElement("afterend", caret);
+
+        let touched = false;
+
+        const toggleMenu = (e) => {
+          // Prevent touch + click double fire
+          if (e.type === "click" && touched) {
+            touched = false;
+            return;
+          }
+
+          if (e.type === "touchstart") {
+            touched = true;
+          }
+
+          e.preventDefault();
+          e.stopPropagation();
+
+          const isOpen = item.classList.toggle("open");
+          caret.setAttribute("aria-expanded", isOpen);
+        };
+
+        // ✅ Only caret toggles menu (link still navigates)
+        caret.addEventListener("touchstart", toggleMenu, { passive: false });
+        caret.addEventListener("click", toggleMenu);
+      });
+    },
+  };
 })(Drupal, once);