fix(home): share styles in the browser email preview

[harlan-zw]

🔗 Linked issue

Related to #644 and NuxtSEO Action 01M4BXGA14G6G789MPVJ3Q3XBK.

❓ Type of change

• 📖 Documentation
• 🐞 Bug fix
• 👌 Enhancement
• ✨ New feature
• 🧹 Chore
• ⚠️ Breaking change

📚 Description

The live homepage still exceeds the 100 KiB payload limit after its feed data grows.
The browser email preview now shares repeated styles through one stylesheet instead of serializing them with every element.
Email delivery keeps its inline styles. Unknown preview styles keep their inline fallback.

The captured homepage payload shrinks from 103,159 to 94,637 bytes.
The shared stylesheet adds 3,602 bytes to the page head.

🤖 AI disclosure: Harlan Agent Kit modified this description. My AI open-source policy.

[harlan-zw]

Agent-written evidence for head 7abbc3b021249c0fb8a758e7855efd2386f45c66.

The production deployment of #644 passed. Four listed payloads cleared 102,400 bytes.
The homepage measured 103,159 bytes after its changing feed data grew beyond the captured replay.

This fix moves known browser preview styles to one shared stylesheet. Cached API cards remain compatible.
The exact captured payload reproduces byte-for-byte before transformation and measures 94,637 bytes afterward.
The card shrinks from 15,925 to 7,429 bytes. Its stylesheet adds 3,602 bytes to the page head.
Email delivery and demo records remain unchanged.

The size regression failed before wiring the transform. All 4,021 tests, lint, typecheck, and build passed.
Browser comparison found no differences across 118 elements in light and dark modes, on desktop and at 360px.
Text, links, image attributes, and unknown-style fallbacks are covered.
The built local homepage emits the stylesheet. Its seeded source had no preview rows.

The public GitHub read credential reached its API quota during CI watching. Remote CI remains unconfirmed by this Agent.
After merge and normal deployment, remeasure the five URLs before claiming the exact Action artifact.
This evidence covers five listed URLs. It does not establish all 245 pages.

[harlan-github-agent]

🤖 MERGED

Harlan Agent Kit posted this automated review. It is not Harlan's personal review or approval. AI open source policy. Last updated: 2026-10-13 16:33 UTC.

GitHub merged this pull request.

No material findings were recorded.

The pull request closed.