Support the mathematical expressions (cotes2020#55).

Author: cotes2020

Diff for: README.md

@@ -28,6 +28,7 @@ A minimal, sidebar, responsive web design Jekyll theme, focusing on text present
 * Table of Contents
 * Automatically recommend related posts
 * Syntax highlighting
+* Mathematical expressions
 * Search
 * Atom Feeds
 * Disqus Comments
@@ -39,7 +40,7 @@ A minimal, sidebar, responsive web design Jekyll theme, focusing on text present
 
 ### Prerequisites
 
-Follow the [Jekyll Docs](https://jekyllrb.com/docs/installation/) to complete the installtion of basic environment (`Ruby `, `RubyGems` and `Bundler`). 
+Follow the [Jekyll Docs](https://jekyllrb.com/docs/installation/) to complete the installtion of basic environment (`Ruby`, `RubyGems` and `Bundler`). 
 
 To improve the writing experience, we need to use some script tools. If your machine is running Debian or macOS, make sure that [GNU coreutils](https://www.gnu.org/software/coreutils/) is installed. Otherwise, install by:
 

Diff for: _includes/head.html

@@ -100,15 +100,19 @@
       <link rel="stylesheet" href="{{ site.baseurl }}/assets/lib/bootstrap-toc-1.0.1/bootstrap-toc.min.css" />
     {% endif %}
 
-  {% endif %}
+    {% if page.math %}
+      <!-- MathJax -->
+      <script src="https://polyfill.io/v3/polyfill.min.js?features=es6"></script>
+      <script src="https://cdn.jsdelivr.net/npm/mathjax@3/es5/tex-mml-chtml.js" async></script>
+    {% endif %}
 
+  {% endif %}
 
   <link rel="preload" as="script"
     href="https://cdn.jsdelivr.net/combine/npm/jquery@3.4.1,npm/popper.js@1.15.0,npm/bootstrap@4.0.0/dist/js/bootstrap.min.js" crossorigin>
 
   <script src="https://cdn.jsdelivr.net/combine/npm/jquery@3.4.1,npm/popper.js@1.15.0,npm/bootstrap@4.0.0/dist/js/bootstrap.min.js"></script>
 
-
   <script src="{{ site.baseurl }}/assets/js/dist/commons.js" async></script>
 
   {% if page.layout == 'home' or page.layout == 'post' %}

Diff for: _posts/2019-08-08-text-and-typography.md

@@ -4,9 +4,10 @@ author: Cotes Chung
 date: 2019-08-08 11:33:00 +0800
 categories: [Blogging, Demo]
 tags: [typography]
+math: true
 ---
 
-This Jekyll template totally compatible with Markdown syntax. Now, let's take a look for the text and typography in this theme.
+This Jekyll template totally compatible with Markdown syntax. Now, let's take a look for the text and typography in here.
 
 ## Titles
 
@@ -49,7 +50,7 @@ Fluttering and dancing in the breeze.
 
 ## Link
 
-[http://127.0.0.1:4000](http://127.0.0.1:4000)
+<http://127.0.0.1:4000>
 
 
 ## Footnote
@@ -66,6 +67,15 @@ Click the hook will locate the footnote[^footnote].
 
 This is an example of `Inline Code`.
 
+## Mathematics
+
+The mathematics powered by [**MathJax**](https://www.mathjax.org/):
+
+$$ \sum_{n=1}^\infty 1/n^2 = \frac{\pi^2}{6} $$
+
+When \\(a \ne 0\\), there are two solutions to \\(ax^2 + bx + c = 0\\) and they are
+
+$$ x = {-b \pm \sqrt{b^2-4ac} \over 2a} $$
 
 ## Code Snippet
 

Diff for: _posts/2019-08-08-write-a-new-post.md

@@ -113,6 +113,17 @@ comments: false
 ```
 
 
+## Mathematics
+
+For website performance reasons, the mathematical feature won't be loaded by default. But it can be enabled by:
+
+```yaml
+---
+math: true
+---
+```
+
+
 ## Code Block
 
 Markdown symbols <code class="highlighter-rouge">```</code> can easily create a code block as following examples.
@@ -136,7 +147,7 @@ items:
       quantity:  4
 ```
 
-#### Liquid codes
+#### Liquid Codes
 
 If you want to display the **Liquid** snippet, surround the liquid code with `{% raw %}{%{% endraw %} raw {%raw%}%}{%endraw%}` and `{% raw %}{%{% endraw %} endraw {%raw%}%}{%endraw%}` .
 
@@ -148,6 +159,8 @@ If you want to display the **Liquid** snippet, surround the liquid code with `{%
 ```
 {% endraw %}
 
+
 ## Learn More
+
 For more knowledge about Jekyll posts, visit the [Jekyll Docs: Posts](https://jekyllrb.com/docs/posts/).