diff --git a/app/composables/useScrollCollapse.ts b/app/composables/useScrollCollapse.ts
index 1aa5064..0d562e5 100644
--- a/app/composables/useScrollCollapse.ts
+++ b/app/composables/useScrollCollapse.ts
@@ -1,55 +1,66 @@
 /**
- * Composable for collapsing header on scroll
- * Returns isCollapsed state that becomes true when scroll > threshold
- * User can manually override the collapsed state
+ * Composable for smooth header collapse on scroll
+ * Returns pixel positions for all fixed layers
  */
-export const useScrollCollapse = (threshold = 50) => {
-  const isCollapsed = ref(false)
+export const useScrollCollapse = (headerHeight = 112, searchBarHeight = 48) => {
   const scrollY = ref(0)
-  const manualOverride = ref(false)
+
+  // Layer positions in pixels
+  // Layers 1+2 (MainNav + SubNav): slide up as user scrolls
+  const headerOffset = computed(() => -Math.min(scrollY.value, headerHeight))
+
+  // Layer 3 (SearchBar): slides down to top:0
+  const searchBarTop = computed(() => Math.max(0, headerHeight - scrollY.value))
+
+  // Layer 4 (Map): follows SearchBar, minimum is searchBarHeight
+  const mapTop = computed(() => Math.max(searchBarHeight, headerHeight + searchBarHeight - scrollY.value))
+
+  // Content padding-top
+  const contentPaddingTop = computed(() => Math.max(searchBarHeight, headerHeight + searchBarHeight - scrollY.value))
+
+  // Is header fully collapsed?
+  const isCollapsed = computed(() => scrollY.value >= headerHeight)
+
+  // Expand - scroll to top
+  const expand = () => {
+    if (import.meta.client) {
+      window.scrollTo({ top: 0, behavior: 'smooth' })
+    }
+  }
+
+  // Collapse - scroll down to hide header
+  const collapse = () => {
+    if (import.meta.client) {
+      window.scrollTo({ top: headerHeight, behavior: 'smooth' })
+    }
+  }
 
   const onScroll = () => {
-    if (import.meta.server) return
-
-    scrollY.value = window.scrollY
-
-    // Only auto-collapse if user hasn't manually expanded
-    if (!manualOverride.value) {
-      isCollapsed.value = scrollY.value > threshold
+    if (import.meta.client) {
+      scrollY.value = window.scrollY
     }
-
-    // Reset manual override when scrolling back to top
-    if (scrollY.value <= threshold) {
-      manualOverride.value = false
-      isCollapsed.value = false
-    }
-  }
-
-  // Manual expand (user clicked chevron down)
-  const expand = () => {
-    isCollapsed.value = false
-    manualOverride.value = true
-  }
-
-  // Manual collapse (user clicked chevron up)
-  const collapse = () => {
-    isCollapsed.value = true
-    manualOverride.value = false
   }
 
   onMounted(() => {
-    window.addEventListener('scroll', onScroll, { passive: true })
-    // Initial check
-    onScroll()
+    if (import.meta.client) {
+      window.addEventListener('scroll', onScroll, { passive: true })
+      onScroll() // Initial value
+    }
   })
 
   onUnmounted(() => {
-    window.removeEventListener('scroll', onScroll)
+    if (import.meta.client) {
+      window.removeEventListener('scroll', onScroll)
+    }
   })
 
   return {
-    isCollapsed: readonly(isCollapsed),
     scrollY: readonly(scrollY),
+    headerOffset,
+    searchBarTop,
+    mapTop,
+    contentPaddingTop,
+    isCollapsed,
     expand,
     collapse
   }
diff --git a/app/layouts/catalog.vue b/app/layouts/catalog.vue
index e964d1d..f6030ce 100644
--- a/app/layouts/catalog.vue
+++ b/app/layouts/catalog.vue
@@ -1,22 +1,9 @@
 <template>
   <div class="min-h-screen bg-base-200">
-    <!-- Layer 1: Collapsed bar (when scrolled) -->
+    <!-- Layer 1+2: MainNavigation + SubNavigation (slides up on scroll) -->
     <div
-      v-if="isHeaderCollapsed"
-      class="fixed top-0 left-0 right-0 z-50 bg-base-200 border-b border-base-300 h-8 flex items-center px-4 lg:px-6"
-    >
-      <button
-        class="btn btn-ghost btn-xs btn-circle"
-        @click="expandHeader"
-      >
-        <Icon name="lucide:chevron-down" size="16" />
-      </button>
-    </div>
-
-    <!-- Layer 1: MainNavigation (fixed) -->
-    <div
-      v-show="!isHeaderCollapsed"
-      class="fixed top-0 left-0 right-0 z-50"
+      class="fixed left-0 right-0 z-50"
+      :style="{ top: `${headerOffset}px` }"
     >
       <MainNavigation
         class="bg-base-200"
@@ -33,52 +20,50 @@
         @sign-in="signIn()"
         @switch-team="switchToTeam"
       />
-    </div>
 
-    <!-- Layer 2: SubNavigation (fixed) -->
-    <div
-      v-show="!isHeaderCollapsed"
-      class="fixed top-16 left-0 right-0 z-40 bg-base-200 border-b border-base-300"
-    >
-      <div class="flex items-center gap-1 py-2 px-4 lg:px-6">
-        <!-- Collapse button -->
-        <button
-          class="btn btn-ghost btn-xs btn-circle mr-1 flex-shrink-0"
-          @click="collapseHeader"
-        >
-          <Icon name="lucide:chevron-up" size="16" />
-        </button>
-
-        <NuxtLink
-          v-for="item in subNavItems"
-          :key="item.path"
-          :to="localePath(item.path)"
-          class="px-4 py-2 rounded-full text-sm font-medium transition-colors whitespace-nowrap text-base-content/70 hover:text-base-content hover:bg-base-300"
-          :class="{ 'text-primary bg-primary/10': isSubNavActive(item.path) }"
-        >
-          {{ item.label }}
-        </NuxtLink>
+      <!-- SubNavigation -->
+      <div class="bg-base-200 border-b border-base-300">
+        <div class="flex items-center gap-1 py-2 px-4 lg:px-6">
+          <NuxtLink
+            v-for="item in subNavItems"
+            :key="item.path"
+            :to="localePath(item.path)"
+            class="px-4 py-2 rounded-full text-sm font-medium transition-colors whitespace-nowrap text-base-content/70 hover:text-base-content hover:bg-base-300"
+            :class="{ 'text-primary bg-primary/10': isSubNavActive(item.path) }"
+          >
+            {{ item.label }}
+          </NuxtLink>
+        </div>
       </div>
     </div>
 
-    <!-- Layer 3: SearchBar (fixed) - teleport target -->
+    <!-- Layer 3: SearchBar (fixed, slides to top:0) - teleport target -->
     <div
       id="catalog-searchbar"
-      class="fixed left-0 right-0 z-30 bg-base-100 border-b border-base-300"
-      :class="isHeaderCollapsed ? 'top-8' : 'top-[6.75rem]'"
-    />
+      class="fixed left-0 right-0 z-40 bg-base-100 border-b border-base-300 flex items-center"
+      :style="{ top: `${searchBarTop}px` }"
+    >
+      <!-- Chevron button inside SearchBar -->
+      <button
+        class="btn btn-ghost btn-xs btn-circle ml-4 flex-shrink-0"
+        @click="isCollapsed ? expand() : collapse()"
+      >
+        <Icon :name="isCollapsed ? 'lucide:chevron-down' : 'lucide:chevron-up'" size="16" />
+      </button>
+      <!-- SearchBar content teleported here -->
+    </div>
 
     <!-- Layer 4: Map (fixed, right side, to bottom) - teleport target -->
     <div
       id="catalog-map"
       class="fixed right-0 bottom-0 w-3/5 z-20 hidden lg:block"
-      :class="isHeaderCollapsed ? 'top-[5.75rem]' : 'top-[9.75rem]'"
+      :style="{ top: `${mapTop}px` }"
     />
 
-    <!-- Content area (left side, with padding for fixed header) -->
+    <!-- Content area (left side, with dynamic padding for fixed header) -->
     <div
       class="lg:w-2/5 min-h-screen"
-      :class="isHeaderCollapsed ? 'pt-[6.75rem]' : 'pt-[10.75rem]'"
+      :style="{ paddingTop: `${contentPaddingTop}px` }"
     >
       <div class="px-4 lg:px-6 py-4">
         <slot />
@@ -110,7 +95,7 @@
       v-if="mobileView === 'map'"
       id="catalog-map-mobile"
       class="lg:hidden fixed inset-0 z-20"
-      :class="isHeaderCollapsed ? 'top-[5.75rem]' : 'top-[9.75rem]'"
+      :style="{ top: `${mapTop}px` }"
     />
   </div>
 </template>
@@ -123,12 +108,16 @@ const route = useRoute()
 const localePath = useLocalePath()
 const { t } = useI18n()
 
-// Collapsible header
-const { isCollapsed, expand, collapse } = useScrollCollapse(50)
-const isHeaderCollapsed = computed(() => isCollapsed.value)
-
-const expandHeader = () => expand()
-const collapseHeader = () => collapse()
+// Smooth collapsible header - headerHeight = 112px (64 + 48), searchBarHeight = 48px
+const {
+  headerOffset,
+  searchBarTop,
+  mapTop,
+  contentPaddingTop,
+  isCollapsed,
+  expand,
+  collapse
+} = useScrollCollapse(112, 48)
 
 // Mobile view toggle
 const mobileView = ref<'list' | 'map'>('list')
@@ -180,7 +169,7 @@ const isSubNavActive = (path: string) => {
 }
 
 // Provide collapsed state to children
-provide('headerCollapsed', isHeaderCollapsed)
+provide('headerCollapsed', isCollapsed)
 
 // Avatar generation
 const generateUserAvatar = async (seed: string) => {