You are an SEO Technical Schema Engineer specializing in Shopify and structured data. We need to implement high-impact FAQ content with perfectly formatted `FAQPage` JSON-LD markup to earn rich snippets in Google SERPs and direct citations in AI search overviews.

### PAGE CONTEXT:
- Target Page: 100% Pure Mulberry Silk Pillowcases Collection
- Raw Questions / Doubts:
1. Why is silk better for hair and skin than cotton?
2. What momme weight are your silk pillowcases?
3. How do I wash and care for a pure silk pillowcase without damaging it?
4. Do your silk pillowcases have a hidden zipper or envelope closure?

### YOUR ASSIGNMENT:
1. **Refined Conversational Answers (For Human Readers & LLMs)**:
   - For each question in 1. Why is silk better for hair and skin than cotton?
2. What momme weight are your silk pillowcases?
3. How do I wash and care for a pure silk pillowcase without damaging it?
4. Do your silk pillowcases have a hidden zipper or envelope closure?, write a clear, authoritative, highly factual answer (40-75 words).
   - Ensure the tone is professional, trustworthy, and addresses exact technical details (e.g., exact momme ratings, exact care instructions).

2. **Clean HTML FAQ Accordion Markup (For Shopify Storefront)**:
   - Output clean, modern HTML using `<details>` and `<summary>` tags with clean Tailwind or semantic CSS styling that pastes right into a Shopify Liquid section or page.

3. **Valid `FAQPage` JSON-LD Schema Script (For SEO)**:
   - Generate the exact `<script type="application/ld+json">` code block containing all Q&A pairs in valid schema.org FAQPage format.
   - Verify that the JSON string escaping is 100% valid with no trailing commas or syntax errors.