Simple Web Word-to-PDF Tool

I want a lightweight website that lets visitors upload a single .docx file and immediately download a PDF containing only the document’s plain text. Images, tables, fonts, and layout details can be ignored completely—the PDF should show the text in the right order with basic paragraph breaks, nothing more.

Here is the flow I have in mind:
• User lands on a clean page, chooses a .docx file, clicks “Convert,” and receives the PDF without any extra steps.
• The server validates that the file is indeed .docx; anything else should trigger a friendly error message.
• Conversion removes all non-text elements before generating the PDF.

Deliverables I expect:
1. A simple front-end page (HTML/CSS/JS) for upload and download.
2. Back-end code that performs the .docx-to-plain-text-to-PDF conversion. Feel free to use Python (Flask, docx2txt, ReportLab), Node.js, PHP, or another stack you prefer, as long as it runs on a standard Linux host.
3. A short README with setup steps and any required libraries so I can deploy the site myself.

Acceptance criteria:
• Files up to roughly 10 MB convert in a single request.
• Resulting PDFs include only the text, with basic line and paragraph breaks preserved.
• No images, tables, or styling appear in the PDF.
• Non-.docx uploads prompt a clear validation message without crashing the app.

Clean, well-commented code is important, as I may tweak or extend the tool later. If you have questions about specifics, let me know before you start.