This is a complete, single-file solution that meets all specified requirements. It uses Tailwind CSS for styling, Lucide for icons, and `ethers.js` for robust Ethereum RLP parsing.
Save the following code as an `.html` file and open it in any browser.
```html
Free Ethereum Raw Transaction RLP Decoder & Parser
Free Ethereum Raw Transaction RLP Decoder & Parser
Instantly decode and inspect complex RLP hexadecimal strings in a structured, easy-to-read format.