feat: convert intro page rwd to Playwright (freeCodeCamp#54666)

e2e/intro-page-rwd.spec.ts

@@ -0,0 +1,47 @@
+import { test, expect } from '@playwright/test';
+
+test.describe('Certification intro page', () => {
+  test('Should render and toggle correctly', async ({ page }) => {
+    const title = page.getByRole('button', {
+      name: 'Learn HTML by Building a Cat Photo App'
+    });
+
+    await page.goto('/learn/2022/responsive-web-design');
+
+    await expect(page).toHaveTitle(
+      'Responsive Web Design Certification | freeCodeCamp.org'
+    );
+
+    await expect(
+      page.getByText(
+        "this Responsive Web Design Certification, you'll learn the languages that developers use to build webpages"
+      )
+    ).toBeVisible();
+
+    await expect(
+      page.getByText(
+        'HTML tags give a webpage its structure. You can use HTML tags to add photos, buttons, and other elements to your webpage.'
+      )
+    ).toBeVisible();
+
+    await expect(
+      page.getByText(
+        'CSS tells the browser how to display your webpage. You can use CSS to set the color, font, size, and other aspects of HTML elements.'
+      )
+    ).not.toBeVisible();
+
+    await title.click();
+    await expect(
+      page.getByText(
+        'HTML tags give a webpage its structure. You can use HTML tags to add photos, buttons, and other elements to your webpage.'
+      )
+    ).not.toBeVisible();
+
+    await title.click();
+    await expect(
+      page.getByText(
+        'HTML tags give a webpage its structure. You can use HTML tags to add photos, buttons, and other elements to your webpage.'
+      )
+    ).toBeVisible();
+  });
+});