diff --git a/src/components/VideoPlayer.test.tsx b/src/components/VideoPlayer.test.tsx
index 173bbfb..29da3cd 100644
--- a/src/components/VideoPlayer.test.tsx
+++ b/src/components/VideoPlayer.test.tsx
@@ -1,6 +1,5 @@
 import { describe, it, expect, vi } from 'vitest';
-import { render, screen, waitFor } from '@testing-library/react';
-import userEvent from '@testing-library/user-event';
+import { render, waitFor } from '@testing-library/react';
 import { VideoPlayer } from './VideoPlayer';
 
 describe('VideoPlayer', () => {
diff --git a/src/utils/corsHelper.test.ts b/src/utils/corsHelper.test.ts
index f9d46c7..94e727a 100644
--- a/src/utils/corsHelper.test.ts
+++ b/src/utils/corsHelper.test.ts
@@ -144,7 +144,7 @@ describe('corsHelper', () => {
 
   describe('checkVideoCORS', () => {
     beforeEach(() => {
-      global.fetch = vi.fn();
+      globalThis.fetch = vi.fn();
     });
 
     afterEach(() => {
@@ -152,7 +152,7 @@ describe('corsHelper', () => {
     });
 
     it('returns supported when CORS headers are present', async () => {
-      (global.fetch as any).mockResolvedValue({
+      (globalThis.fetch as any).mockResolvedValue({
         ok: true,
         headers: new Map([
           ['Access-Control-Allow-Origin', '*'],
@@ -167,7 +167,7 @@ describe('corsHelper', () => {
     });
 
     it('returns not supported when CORS headers are missing', async () => {
-      (global.fetch as any).mockResolvedValue({
+      (globalThis.fetch as any).mockResolvedValue({
         ok: false,
         headers: new Map(),
       });
@@ -179,7 +179,7 @@ describe('corsHelper', () => {
     });
 
     it('detects range support', async () => {
-      (global.fetch as any).mockResolvedValue({
+      (globalThis.fetch as any).mockResolvedValue({
         ok: true,
         headers: new Map([
           ['Access-Control-Allow-Origin', '*'],
@@ -192,7 +192,7 @@ describe('corsHelper', () => {
     });
 
     it('detects no range support when header is "none"', async () => {
-      (global.fetch as any).mockResolvedValue({
+      (globalThis.fetch as any).mockResolvedValue({
         ok: true,
         headers: new Map([
           ['Access-Control-Allow-Origin', '*'],
@@ -205,7 +205,7 @@ describe('corsHelper', () => {
     });
 
     it('handles CORS fetch errors', async () => {
-      (global.fetch as any).mockRejectedValue(new TypeError('Failed to fetch (CORS)'));
+      (globalThis.fetch as any).mockRejectedValue(new TypeError('Failed to fetch (CORS)'));
 
       const result = await checkVideoCORS('https://example.com/video.mp4');
       expect(result.supported).toBe(false);
@@ -214,7 +214,7 @@ describe('corsHelper', () => {
     });
 
     it('handles general fetch errors', async () => {
-      (global.fetch as any).mockRejectedValue(new Error('Network error'));
+      (globalThis.fetch as any).mockRejectedValue(new Error('Network error'));
 
       const result = await checkVideoCORS('https://example.com/video.mp4');
       expect(result.supported).toBe(false);