diff --git a/src/app/pages/category/._category.component.ts b/src/app/pages/category/._category.component.ts
new file mode 100644
index 0000000..707ba9b
Binary files /dev/null and b/src/app/pages/category/._category.component.ts differ
diff --git a/src/app/pages/category/._subcategories.component.ts b/src/app/pages/category/._subcategories.component.ts
new file mode 100644
index 0000000..707ba9b
Binary files /dev/null and b/src/app/pages/category/._subcategories.component.ts differ
diff --git a/src/app/pages/category/category.component.ts b/src/app/pages/category/category.component.ts
index e3b51ba..e7c13dd 100644
--- a/src/app/pages/category/category.component.ts
+++ b/src/app/pages/category/category.component.ts
@@ -40,7 +40,17 @@ export class CategoryComponent implements OnInit, OnDestroy {
 
   ngOnInit(): void {
     this.routeSubscription = this.route.params.subscribe(params => {
-      const id = parseInt(params['id'], 10);
+      const id = Number.parseInt(params['id'], 10);
+
+      if (!Number.isFinite(id) || id <= 0) {
+        this.error.set('Invalid category ID');
+        this.items.set([]);
+        this.hasMore.set(false);
+        this.loading.set(false);
+        this.isLoadingMore = false;
+        return;
+      }
+
       this.categoryID.set(id);
       this.resetAndLoad();
     });
diff --git a/src/app/pages/category/subcategories.component.ts b/src/app/pages/category/subcategories.component.ts
index 1146b10..805963f 100644
--- a/src/app/pages/category/subcategories.component.ts
+++ b/src/app/pages/category/subcategories.component.ts
@@ -41,7 +41,18 @@ export class SubcategoriesComponent implements OnInit, OnDestroy {
 
   ngOnInit(): void {
     this.routeSubscription = this.route.params.subscribe(params => {
-      const id = parseInt(params['id'], 10);
+      const id = Number.parseInt(params['id'], 10);
+
+      if (!Number.isFinite(id) || id <= 0) {
+        this.error.set('Invalid category ID');
+        this.categories.set([]);
+        this.subcategories.set([]);
+        this.nestedSubcategories.set([]);
+        this.categoryItems.set([]);
+        this.loading.set(false);
+        return;
+      }
+
       this.loadForParent(id);
     });
   }