feat: Add About Us page, dark theme, and main page navigation (#14)

[shreyashx16]

Description

This PR adds a new About Us page to the DevUI Components project, implements a cohesive dark theme, and introduces an "About Us" button on the main page for easy navigation.

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✅ What’s Included

• New app/about/page.tsx with:

  • Project introduction, mission, and features
  • Modern dark gradient background with subtle accent colors
  • Responsive layout with shadcn/ui components
  • Demo placeholder text for future content
  • “Back to Home” button

• Added an “About Us” button to the main page hero section for direct navigation

• Implemented and styled the Separator component for section separation

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📸 Screenshots

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🧪 How to Test

1. Run the project:

   npm run dev

2. Visit /about to view the new About Us page.

3. From the main page (/), click the “About Us” button to navigate.

4. Verify:

   • Dark theme styling is consistent
   • Layout is responsive (mobile + desktop)
   • Demo text and components render correctly

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🔗 Related Issue

Closes #14

[fahimahammed]

Build failed. Please sync your repo, pull the latest changes from the main branch, then push your code. I’ll review the PR in about 15 minutes.

[shreyashx16]

Hi @fahimahammed! I noticed two issues with the CI/CD workflows on my PR:
Vercel Preview Build Failed:
The workflow failed with the error: Error: No existing credentials found. Please run vercel login or pass "--token"

This means the Vercel CLI in the workflow doesn’t have the required authentication token. Only someone with access to the Vercel project can add the VERCEL_TOKEN as a GitHub Actions secret and update the workflow to use it.

add-badge/label Action Failed:
The workflow failed with: Error: HttpError: Resource not accessible by integration

This usually happens because the GitHub Actions workflow doesn’t have permission to add labels when running on a fork, or the workflow permissions are set to read-only. Only a maintainer can update the repo settings to allow this, or run the workflow from the main repo.

Both issues are related to repository/workflow permissions and not to my code.