diff --git a/src/app/components/create-dialog/create-dialog.component.ts b/src/app/components/create-dialog/create-dialog.component.ts
index 4123536..7b5bdce 100644
--- a/src/app/components/create-dialog/create-dialog.component.ts
+++ b/src/app/components/create-dialog/create-dialog.component.ts
@@ -16,6 +16,7 @@ export interface CreateDialogData {
     type: 'text' | 'number' | 'toggle';
     required?: boolean;
     value?: any;
+    hint?: string;
   }[];
 }
 
@@ -50,6 +51,9 @@ export interface CreateDialogData {
                 [type]="field.type"
                 [(ngModel)]="formData[field.name]"
                 [required]="!!field.required">
+              @if (field.hint) {
+                <mat-hint>{{ field.hint }}</mat-hint>
+              }
               @if (field.required && !formData[field.name]) {
                 <mat-error>{{ field.label }} is required</mat-error>
               }
diff --git a/src/app/models/category.model.ts b/src/app/models/category.model.ts
index 1dfebd9..aef5c5a 100644
--- a/src/app/models/category.model.ts
+++ b/src/app/models/category.model.ts
@@ -14,7 +14,10 @@ export interface Subcategory {
   visible: boolean;
   priority: number;
   img?: string;
+  /** Root-level category this subcategory belongs to */
   categoryId: string;
+  /** Direct parent ID — could be a category ID or a parent subcategory ID */
+  parentId?: string;
   itemCount?: number;
   subcategories?: Subcategory[];
   hasItems?: boolean;
diff --git a/src/app/pages/category-editor/category-editor.component.ts b/src/app/pages/category-editor/category-editor.component.ts
index 7f17c12..5ed9029 100644
--- a/src/app/pages/category-editor/category-editor.component.ts
+++ b/src/app/pages/category-editor/category-editor.component.ts
@@ -143,7 +143,7 @@ export class CategoryEditorComponent implements OnInit {
 
     dialogRef.afterClosed().subscribe(result => {
       if (result) {
-        this.apiService.createSubcategory(this.categoryId(), result).subscribe({
+          this.apiService.createSubcategory(this.categoryId(), 'category', result).subscribe({
           next: () => {
             this.snackBar.open('Subcategory created!', 'Close', { duration: 2000 });
             this.loadCategory();
diff --git a/src/app/pages/item-editor/item-editor.component.scss b/src/app/pages/item-editor/item-editor.component.scss
index ae67471..c5c83cb 100644
--- a/src/app/pages/item-editor/item-editor.component.scss
+++ b/src/app/pages/item-editor/item-editor.component.scss
@@ -61,7 +61,6 @@
   gap: 1.5rem;
   background-color: #fff;
   border-radius: 0 0 8px 8px;
-  gap: 1.5rem;
 
   .full-width {
     width: 100%;
diff --git a/src/app/pages/item-editor/item-editor.component.ts b/src/app/pages/item-editor/item-editor.component.ts
index f1cbf1a..64b230e 100644
--- a/src/app/pages/item-editor/item-editor.component.ts
+++ b/src/app/pages/item-editor/item-editor.component.ts
@@ -125,17 +125,21 @@ export class ItemEditorComponent implements OnInit {
         
         pathSegments.unshift(subcategory.id); // Add to beginning
         
-        // Check if this subcategory has a parent subcategory or belongs to a category
-        if (subcategory.categoryId && subcategory.categoryId.startsWith('cat')) {
-          // This is directly under a category, add category and stop
+        // parentId = direct parent (another subcategory or the root category)
+        // categoryId = always the root category
+        const isDirectCategoryChild =
+          !subcategory.parentId || subcategory.parentId === subcategory.categoryId;
+
+        if (isDirectCategoryChild) {
+          // This subcategory sits directly under a root category
           const category = await this.apiService.getCategory(subcategory.categoryId).toPromise();
           if (category) {
             pathSegments.unshift(category.id);
           }
           break;
         } else {
-          // This is under another subcategory, continue traversing
-          currentSubcategoryId = subcategory.categoryId;
+          // Still inside a parent subcategory — keep traversing up
+          currentSubcategoryId = subcategory.parentId!;
         }
       } catch (err) {
         console.error('Error building path:', err);
diff --git a/src/app/pages/items-list/items-list.component.html b/src/app/pages/items-list/items-list.component.html
index fa43bbc..dd0dc18 100644
--- a/src/app/pages/items-list/items-list.component.html
+++ b/src/app/pages/items-list/items-list.component.html
@@ -3,7 +3,7 @@
     <button mat-icon-button (click)="goBack()">
       <mat-icon>arrow_back</mat-icon>
     </button>
-    <span class="toolbar-title">Items List</span>
+    <span class="toolbar-title">{{ subcategoryName() || 'Items' }}</span>
     <span class="toolbar-spacer"></span>
     <button mat-mini-fab color="accent" (click)="addItem()">
       <mat-icon>add</mat-icon>
@@ -133,4 +133,6 @@
       <p>No items found</p>
     </div>
   }
+
+  <div #scrollSentinel class="scroll-sentinel"></div>
 </div>
diff --git a/src/app/pages/items-list/items-list.component.scss b/src/app/pages/items-list/items-list.component.scss
index 4194060..b388f82 100644
--- a/src/app/pages/items-list/items-list.component.scss
+++ b/src/app/pages/items-list/items-list.component.scss
@@ -13,6 +13,10 @@
     font-size: 1.25rem;
     font-weight: 500;
   }
+
+  .toolbar-spacer {
+    flex: 1;
+  }
 }
 
 .filters-bar {
@@ -267,3 +271,8 @@
     margin: 0;
   }
 }
+
+.scroll-sentinel {
+  height: 4px;
+  width: 100%;
+}
diff --git a/src/app/pages/items-list/items-list.component.ts b/src/app/pages/items-list/items-list.component.ts
index dd08c24..2e23999 100644
--- a/src/app/pages/items-list/items-list.component.ts
+++ b/src/app/pages/items-list/items-list.component.ts
@@ -1,4 +1,4 @@
-import { Component, OnInit, signal, HostListener } from '@angular/core';
+import { Component, OnInit, AfterViewInit, OnDestroy, signal, ViewChild, ElementRef } from '@angular/core';
 import { ActivatedRoute, Router } from '@angular/router';
 import { CommonModule } from '@angular/common';
 import { FormsModule } from '@angular/forms';
@@ -39,14 +39,18 @@ import { ConfirmDialogComponent } from '../../components/confirm-dialog/confirm-
   templateUrl: './items-list.component.html',
   styleUrls: ['./items-list.component.scss']
 })
-export class ItemsListComponent implements OnInit {
+export class ItemsListComponent implements OnInit, AfterViewInit, OnDestroy {
   items = signal<Item[]>([]);
   loading = signal(false);
-  hasMore = signal(true);
+  hasMore = signal(false);
   page = signal(1);
-  searchQuery = signal('');
-  visibilityFilter = signal<boolean | undefined>(undefined);
+  searchQuery = '';
+  visibilityFilter: boolean | undefined = undefined;
   selectedItems = signal<Set<string>>(new Set());
+  subcategoryName = signal<string>('');
+
+  @ViewChild('scrollSentinel') scrollSentinel!: ElementRef;
+  private intersectionObserver?: IntersectionObserver;
   
   subcategoryId = signal<string>('');
   projectId = signal<string>('');
@@ -68,14 +72,17 @@ export class ItemsListComponent implements OnInit {
     
     this.route.params.subscribe(params => {
       this.subcategoryId.set(params['subcategoryId']);
+      this.page.set(1);
+      this.items.set([]);
+      this.selectedItems.set(new Set());
+      this.subcategoryName.set('');
+      this.loadSubcategoryName();
       this.loadItems();
     });
   }
 
   loadItems(append = false) {
-    if (this.loading() || (!append && this.items().length > 0)) {
-      return;
-    }
+    if (this.loading()) return;
 
     this.loading.set(true);
     const currentPage = append ? this.page() + 1 : 1;
@@ -84,9 +91,9 @@ export class ItemsListComponent implements OnInit {
       this.subcategoryId(),
       currentPage,
       20,
-      this.searchQuery() || undefined,
+      this.searchQuery || undefined,
       {
-        visible: this.visibilityFilter(),
+        visible: this.visibilityFilter,
         tags: []
       }
     ).subscribe({
@@ -108,16 +115,31 @@ export class ItemsListComponent implements OnInit {
     });
   }
 
-  @HostListener('window:scroll', [])
-  onScroll() {
-    const scrollPosition = window.pageYOffset + window.innerHeight;
-    const documentHeight = document.documentElement.scrollHeight;
-    
-    if (scrollPosition >= documentHeight - 200 && this.hasMore() && !this.loading()) {
-      this.loadItems(true);
+  ngAfterViewInit() {
+    this.intersectionObserver = new IntersectionObserver(
+      entries => {
+        if (entries[0].isIntersecting && this.hasMore() && !this.loading()) {
+          this.loadItems(true);
+        }
+      },
+      { rootMargin: '200px', threshold: 0 }
+    );
+    if (this.scrollSentinel?.nativeElement) {
+      this.intersectionObserver.observe(this.scrollSentinel.nativeElement);
     }
   }
 
+  ngOnDestroy() {
+    this.intersectionObserver?.disconnect();
+  }
+
+  loadSubcategoryName() {
+    this.apiService.getSubcategory(this.subcategoryId()).subscribe({
+      next: (sub) => this.subcategoryName.set(sub.name),
+      error: () => {}
+    });
+  }
+
   onSearch() {
     this.page.set(1);
     this.items.set([]);
@@ -205,6 +227,8 @@ export class ItemsListComponent implements OnInit {
         this.apiService.createItem(subcategoryId, result).subscribe({
           next: () => {
             this.snackBar.open('Item created successfully', 'Close', { duration: 3000 });
+            this.page.set(1);
+            this.items.set([]);
             this.loadItems();
           },
           error: (err) => {
@@ -234,6 +258,8 @@ export class ItemsListComponent implements OnInit {
         this.apiService.deleteItem(item.id).subscribe({
           next: () => {
             this.snackBar.open('Item deleted successfully', 'Close', { duration: 3000 });
+            this.page.set(1);
+            this.items.set([]);
             this.loadItems();
           },
           error: (err) => {
diff --git a/src/app/pages/project-view/project-view.component.html b/src/app/pages/project-view/project-view.component.html
index af5de17..c5b99b9 100644
--- a/src/app/pages/project-view/project-view.component.html
+++ b/src/app/pages/project-view/project-view.component.html
@@ -3,7 +3,7 @@
     <button mat-icon-button (click)="goBack()">
       <mat-icon>arrow_back</mat-icon>
     </button>
-    <span>Project: {{ projectId() }}</span>
+    <span>{{ project()?.displayName || projectId() }}</span>
   </mat-toolbar>
 
   <mat-sidenav-container class="sidenav-container">
@@ -87,7 +87,7 @@
 </div>
 
 <ng-template #subcategoryTree let-nodes="nodes" let-level="level">
-  <div class="subcategories" [style.padding-left.rem]="level * 1.5">
+  <div class="subcategories">
     @for (subNode of nodes; track subNode.id) {
       <div>
         <div class="node-content subcategory-node" [class.selected]="selectedNodeId() === subNode.id">
diff --git a/src/app/pages/project-view/project-view.component.scss b/src/app/pages/project-view/project-view.component.scss
index f4732ac..698ce02 100644
--- a/src/app/pages/project-view/project-view.component.scss
+++ b/src/app/pages/project-view/project-view.component.scss
@@ -15,7 +15,7 @@ mat-toolbar {
 }
 
 .categories-sidebar {
-  width: 380px;
+  width: 420px;
   border-right: 1px solid #e0e0e0;
   background-color: #fff;
 
@@ -31,6 +31,8 @@ mat-toolbar {
       font-size: 1.25rem;
       font-weight: 500;
     }
+
+    // icon centering handled globally via styles.scss
   }
 
   .loading-container {
@@ -68,6 +70,10 @@ mat-toolbar {
       background-color: #bbdefb;
       border-left: 4px solid #1976d2;
       padding-left: calc(0.5rem - 4px);
+
+      .node-actions {
+        opacity: 1;
+      }
       
       &:hover {
         background-color: #90caf9;
@@ -85,13 +91,12 @@ mat-toolbar {
     }
 
     &.subcategory-node {
-      padding-left: 3rem;
       font-size: 0.95rem;
       background-color: #fff;
-      
+
       &.selected {
         background-color: #bbdefb;
-        padding-left: calc(3rem - 4px);
+        border-left: 4px solid #1976d2;
       }
     }
 
@@ -110,8 +115,8 @@ mat-toolbar {
       align-items: center;
       gap: 0.25rem;
       flex-shrink: 0;
-      opacity: 0.7;
-      transition: opacity 0.2s;
+      opacity: 0;
+      transition: opacity 0.15s;
 
       mat-slide-toggle {
         transform: scale(0.75);
@@ -119,15 +124,16 @@ mat-toolbar {
       }
 
       button {
-        // width: 32px;
-        // height: 32px;
-        // line-height: 32px;
-        
+        --mdc-icon-button-state-layer-size: 30px;
+        --mdc-icon-button-icon-size: 18px;
+        width: 30px;
+        height: 30px;
+        padding: 0;
+
         mat-icon {
           font-size: 18px;
           width: 18px;
           height: 18px;
-          line-height: 18px;
         }
 
         &:hover {
@@ -143,6 +149,10 @@ mat-toolbar {
 
   .subcategories {
     background-color: #fafafa;
+    padding-left: 1rem;
+    border-left: 2px solid #e3e8ef;
+    margin-left: 1.25rem;
+    overflow: hidden;
   }
 }
 
diff --git a/src/app/pages/project-view/project-view.component.ts b/src/app/pages/project-view/project-view.component.ts
index b178728..8800601 100644
--- a/src/app/pages/project-view/project-view.component.ts
+++ b/src/app/pages/project-view/project-view.component.ts
@@ -253,8 +253,8 @@ export class ProjectViewComponent implements OnInit {
           return;
         }
         
-        const parentId = parentNode.type === 'category' ? parentNode.id : parentNode.id;
-        this.apiService.createSubcategory(parentId, result).subscribe({
+        const parentType = parentNode.type === 'category' ? 'category' : 'subcategory';
+        this.apiService.createSubcategory(parentNode.id, parentType, result).subscribe({
           next: () => {
             this.snackBar.open('Subcategory created!', 'Close', { duration: 2000 });
             this.loadCategories();
diff --git a/src/app/pages/subcategory-editor/subcategory-editor.component.html b/src/app/pages/subcategory-editor/subcategory-editor.component.html
index bb42346..0818cb6 100644
--- a/src/app/pages/subcategory-editor/subcategory-editor.component.html
+++ b/src/app/pages/subcategory-editor/subcategory-editor.component.html
@@ -15,11 +15,7 @@
         @if (saving()) {
           <span class="save-indicator">Saving...</span>
         }
-        <button mat-raised-button color="accent" (click)="viewItems()">
-          <mat-icon>list</mat-icon>
-          View Items
-        </button>
-        <button mat-icon-button color="warn" (click)="deleteSubcategory()">
+        <button mat-icon-button color="warn" (click)="deleteSubcategory()" matTooltip="Delete Subcategory">
           <mat-icon>delete</mat-icon>
         </button>
       </div>
@@ -109,10 +105,17 @@
       </div>
 
       <div class="items-section">
-        <button mat-raised-button color="primary" (click)="viewItems()">
-          <mat-icon>list</mat-icon>
-          View Items ({{ subcategory()!.itemCount || 0 }})
-        </button>
+        @if (subcategory()!.subcategories?.length) {
+          <p class="no-items-note">
+            <mat-icon>account_tree</mat-icon>
+            This subcategory has child subcategories — items can only be added to leaf nodes.
+          </p>
+        } @else {
+          <button mat-raised-button color="primary" (click)="viewItems()">
+            <mat-icon>{{ subcategory()!.hasItems ? 'list' : 'add' }}</mat-icon>
+            {{ subcategory()!.hasItems ? 'View Items (' + (subcategory()!.itemCount || 0) + ')' : 'Add Items' }}
+          </button>
+        }
       </div>
     </div>
   }
diff --git a/src/app/pages/subcategory-editor/subcategory-editor.component.scss b/src/app/pages/subcategory-editor/subcategory-editor.component.scss
index aa2a05a..d92317b 100644
--- a/src/app/pages/subcategory-editor/subcategory-editor.component.scss
+++ b/src/app/pages/subcategory-editor/subcategory-editor.component.scss
@@ -115,4 +115,19 @@
     align-items: center;
     gap: 0.5rem;
   }
+
+  .no-items-note {
+    display: flex;
+    align-items: center;
+    gap: 0.5rem;
+    color: #888;
+    font-size: 0.875rem;
+
+    mat-icon {
+      font-size: 18px;
+      width: 18px;
+      height: 18px;
+      color: #bbb;
+    }
+  }
 }
diff --git a/src/app/pages/subcategory-editor/subcategory-editor.component.ts b/src/app/pages/subcategory-editor/subcategory-editor.component.ts
index 9b59273..e6e7b83 100644
--- a/src/app/pages/subcategory-editor/subcategory-editor.component.ts
+++ b/src/app/pages/subcategory-editor/subcategory-editor.component.ts
@@ -142,7 +142,12 @@ export class SubcategoryEditorComponent implements OnInit {
         this.apiService.deleteSubcategory(sub.id).subscribe({
           next: () => {
             this.snackBar.open('Subcategory deleted successfully', 'Close', { duration: 3000 });
-            this.router.navigate(['/project', this.projectId(), 'category', sub.categoryId]);
+            // Navigate to the direct parent (subcategory) if parentId exists, otherwise the root category
+            if (sub.parentId && sub.parentId !== sub.categoryId) {
+              this.router.navigate(['/project', this.projectId(), 'subcategory', sub.parentId]);
+            } else {
+              this.router.navigate(['/project', this.projectId(), 'category', sub.categoryId]);
+            }
           },
           error: (err: any) => {
             console.error('Error deleting subcategory:', err);
diff --git a/src/app/services/api.service.ts b/src/app/services/api.service.ts
index 4bb7adf..1ccbf96 100644
--- a/src/app/services/api.service.ts
+++ b/src/app/services/api.service.ts
@@ -103,9 +103,12 @@ export class ApiService {
     );
   }
 
-  createSubcategory(categoryId: string, data: Partial<Subcategory>): Observable<Subcategory> {
-    if (environment.useMockData) return this.mockService.createSubcategory(categoryId, data);
-    return this.http.post<Subcategory>(`${this.API_BASE}/categories/${categoryId}/subcategories`, data).pipe(
+  createSubcategory(parentId: string, parentType: 'category' | 'subcategory', data: Partial<Subcategory>): Observable<Subcategory> {
+    if (environment.useMockData) return this.mockService.createSubcategory(parentId, data);
+    const endpoint = parentType === 'category'
+      ? `${this.API_BASE}/categories/${parentId}/subcategories`
+      : `${this.API_BASE}/subcategories/${parentId}/subcategories`;
+    return this.http.post<Subcategory>(endpoint, data).pipe(
       catchError(this.handleError)
     );
   }
diff --git a/src/app/services/mock-data.service.ts b/src/app/services/mock-data.service.ts
index 3f5c31e..77c4744 100644
--- a/src/app/services/mock-data.service.ts
+++ b/src/app/services/mock-data.service.ts
@@ -273,7 +273,8 @@ export class MockDataService {
       visible: data.visible ?? true,
       priority: data.priority || 99,
       img: data.img,
-      categoryId: parentId,
+      categoryId: parentId, // will be root category ID after backend resolves; mock keeps direct parent for simplicity
+      parentId: parentId,
       itemCount: 0
     };
     
diff --git a/src/styles.scss b/src/styles.scss
index 9d7f90b..e0a6531 100644
--- a/src/styles.scss
+++ b/src/styles.scss
@@ -22,15 +22,41 @@ button[mat-raised-button], button[mat-flat-button] {
   letter-spacing: 0.5px;
 }
 
+// Icon buttons — always center the icon in its circle
 button[mat-icon-button] {
+  display: inline-flex !important;
+  align-items: center !important;
+  justify-content: center !important;
+
+  .mat-icon {
+    display: flex !important;
+    align-items: center !important;
+    justify-content: center !important;
+    margin: 0 !important;
+    padding: 0 !important;
+    line-height: 1 !important;
+  }
+
   &:hover {
     background-color: rgba(0, 0, 0, 0.04);
   }
 }
 
 button[mat-mini-fab] {
+  display: inline-flex !important;
+  align-items: center !important;
+  justify-content: center !important;
   box-shadow: 0 3px 8px rgba(0, 0, 0, 0.25) !important;
-  
+
+  .mat-icon {
+    display: flex !important;
+    align-items: center !important;
+    justify-content: center !important;
+    margin: 0 !important;
+    padding: 0 !important;
+    line-height: 1 !important;
+  }
+
   &:hover {
     box-shadow: 0 5px 12px rgba(0, 0, 0, 0.35) !important;
   }
@@ -55,8 +81,8 @@ mat-card {
 
 // Scrollbar styling
 ::-webkit-scrollbar {
-  width: 10px;
-  height: 10px;
+  width: 6px;
+  height: 6px;
 }
 
 ::-webkit-scrollbar-track {
@@ -64,11 +90,11 @@ mat-card {
 }
 
 ::-webkit-scrollbar-thumb {
-  background: #888;
-  border-radius: 5px;
-  
+  background: #aaa;
+  border-radius: 6px;
+
   &:hover {
-    background: #555;
+    background: #666;
   }
 }
 
@@ -85,6 +111,11 @@ mat-card {
   --mat-snack-bar-button-color: white !important;
 }
 
+// Common editor layout helpers
+.editor-page {
+  padding: 1.5rem 2rem;
+}
+
 .toast-warning {
   --mdc-snackbar-container-color: #ff9800 !important;
   --mdc-snackbar-supporting-text-color: white !important;