Create index.html for this Repository

# Create `index.html` for OS Repository with CSS and JavaScript

## Description
Develop an `index.html` page to showcase information about supported operating systems for LinuxDroid. The webpage should be styled using an external `style.css` file and include interactivity through a `linuxdroid.js` file. Ensure the page is visually appealing, easy to navigate, and responsive across devices.

## Tasks
- [ ] Create an `index.html` file with a clean and semantic structure.
- [ ] Style the webpage using an external `style.css` file.
- [ ] Add interactivity using the `linuxdroid.js` file (if necessary).
- [ ] Include a navigation bar for easy access to different sections of the OS list.
- [ ] Ensure responsiveness for various screen sizes (desktop, tablet, mobile).
- [ ] Test the page across different browsers to ensure compatibility.

## Notes
- The CSS file (`style.css`) should follow best practices for styling, including mobile-first design.
- JavaScript (`linuxdroid.js`) should be lightweight and optimized for performance.

Start at the repository root and inspect the existing project content before creating index.html, style.css, and linuxdroid.js. Define the page structure around supported operating systems, then verify navigation, responsive layouts, lightweight interactivity, and browser compatibility. Done means the requested files exist and the page is usable on desktop, tablet, and mobile.

Written by the indexing model from the issue text.