封面图

---
title: "your-post-title"
# ...
cover:
    image: example.jpg # or URL
    alt: xxx # Optional
    width: 750 # Optional
    height: 500 # Optional
---

---
title: "author-name"
# ...
avatar:
    image: example-avatar.jpg
    alt: Example Avatar
cover:
    image: example-background.jpg
    alt: Example Background Image