Create 404 error page

[dev129]

Here’s a generated Pull Request (PR) message based on your description for GitHub:

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Pull Request: Custom 404 Page Implementation

Issue: #168

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Description:

This Pull Request (PR) introduces a custom 404 "Not Found" page for the CodeIt application, enhancing the user experience when navigating to non-existent pages. The new design ensures a seamless and visually consistent experience.

Key Features:

• User-Friendly Design:
  The custom 404 page presents a clear message indicating that the requested page could not be found. It includes suggestions for next steps, such as returning to the homepage or exploring other sections of the website.

• Consistent Branding:
  The page follows the overall branding of CodeIt, maintaining aesthetic consistency throughout the application.

• Dynamic Logo Display:
  The logo dynamically switches between light and dark modes, based on user preferences, by using the next-themes package. The appropriate logo is shown based on the active theme, ensuring a cohesive look.

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Implementation Details:

• The custom 404 page is located at /pages/error404.html and the css and js files are located in /resources/error404.css and /resources/error404.js.
• The logos for light and dark mode are stored at /images/Nomenclature.png.
• Theme detection is powered by the next-themes package, allowing the correct logo to be displayed in light or dark mode.
• Routing logic has been updated to ensure all undefined routes redirect to this custom 404 page.
• All assets and styling are designed to fit seamlessly within the Codecache application's overall user interface.

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Testing:

• The 404 page has been tested across multiple devices and browsers to ensure proper responsiveness and functionality.
• Verified the logo dynamically changes based on the active theme (light/dark mode).
• Routing to this error page on an error can be set only from the sever side using .htlaccess

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Please review the changes and merge this PR at your earliest convenience.

Thank you!

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This PR message is structured to explain the changes clearly for easy review and provides all necessary information for merging into the main branch.

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[dev129]

Hi @multiverseweb , I have raised the PR, would you please approve my merge request ?