based on the following scheme -- thanks!

image is inserted using the following code

{% if site.image %}
  <div class="cover-image"><img src="{{ site.image }}" alt="" /></div>
{% endif %}

A Jekyll theme.

Demo × Download

Demo images are from Unsplash.

Site cover image:

# _config.yml
image: /crossing-jekyll/images/site-image.jpg

Post cover image:

---
image: /crossing-jekyll/images/post-image.jpg
---

To have author bylines and bio at bottom of posts, add configuration like the following in _config.yml:

authors:
  johndoe:
    name: John Doe
    website: https://github.com/barepants
    bio: An awesome bio # Author info at bottom of post only shows if bio exists
    avatar: /crossing-jekyll/images/avatar.jpg

and specify the author in the Front Matter of posts:

---
author: johndoe
---

Crossing generates Open Graph and Twitter Cards meta tags automatically for better social media sharing. There are two extra settings:

# _config.yml
og_image: /images/og-image.jpg # Fallback og:image when no page.image or site.image. at least 200 x 200px.
twitter_site: # twitter:site. Your Twitter username without "@"

page.excerpt is used for meta description of posts and pages. It is the first paragraph by default for posts. For pages you have to set it in the Front Matter:

---
excerpt: An excerpt
---

Twitter Cards requires meta description. Facebook could infer it from the page if it's empty.

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