📸 Page Elements: Writing content with Markdown, LaTeX, and Shortcodes

Rich content can be written in Wowchemy using Markdown, LaTeX math, and Shortcodes. This article gives an overview of the most common formatting options, including features that are exclusive to Wowchemy.

Sub-headings

After the page title, heading 1, we can format sub-headings in the page body:

## Heading 2
### Heading 3
#### Heading 4

Emphasis

Bold, Italic, Strikethrough

Italics with _underscores_.

Bold with **asterisks**.

Combined emphasis with **asterisks and _underscores_**.

Strikethrough with ~~two tildes~~.

Italics with underscores.

Bold with asterisks.

Combined emphasis with asterisks and underscores.

Strikethrough with two tildes.

Text color

Add the HTML color attribute in the form {style="color: red"} to the line after a Markdown block.

For example, to color a paragraph red:

Red colored text
{style="color: red"}

Blockquote

> This is a blockquote.

This is a blockquote.

Highlight quote

This is a {{< hl >}}highlighted quote{{< /hl >}}.

This is a highlighted quote.

Lists

Ordered

1. First item
   1. A sub-item
2. Another item

1. First item
   1. A sub-item
2. Another item

Unordered

- First item
  - A sub-item
- Another item

• First item
  • A sub-item
• Another item

Todo

Todo lists can be written in Wowchemy by using the standard Markdown syntax:

- [x] Write math example
  - [x] Write diagram example
- [ ] Do something else

renders as

• Write math example
  • Write diagram example
• Do something else

Toggle lists

Add a toggle list to a page to reveal text, such as an answer to a question, after a toggle button is clicked.

Useful for FAQs, spoilers, or hiding answers when teaching online courses.

{{< spoiler text="Click to view the spoiler" >}}
You found me!
{{< /spoiler >}}

renders as

Links

Link to a page

[I'm an external link](https://www.google.com)
[A post]({{< relref "/post/my-page-name" >}})
[A publication]({{< relref "/publication/my-page-name" >}})
[A project]({{< relref "/project/my-page-name" >}})
[A relative link from one post to another post]({{< relref "../my-page-name" >}})
[Scroll down to a page section with heading *Hi*](#hi)

You can also create a button link in the page header of any page except Widget Pages (the homepage).

Link to a file

You can create a button link to a file in the page header of any page except Widget Pages (the homepage).

Otherwise, to link to a file, such as a PDF, in the body of your content, place the file in your static/uploads/ folder and then link to it using the following form:

{{% staticref "uploads/cv.pdf" "newtab" %}}Download my CV{{% /staticref %}}

The optional "newtab" argument for staticref will cause the link to be opened in a new tab.

Cite

To cite a page or publication, you can use the cite shortcode, referencing a folder and page name that you created:

{{< cite page="/publication/preprint" view="4" >}}

where view corresponds to one of the available listing views used throughout Wowchemy:

1. Stream
2. Compact
3. Card
4. Traditional academic citation, configured by the citation_style setting in params.yaml

If you don’t specify a view, it will default to the compact view.

The cite shortcode requires Wowchemy v5+.

Table of Contents

A table of contents can help users navigate long pages.

Paste the {{< toc >}} shortcode wherever you would like a table of contents to appear in your page.

You may also wish to consider using the book layout which displays a built-in table of contents in a right sidebar on large screens.

When using the book layout, you may still wish to add an in-page table of contents which only appears when the right sidebar is hidden. You can do this with {{< toc hide_on="xl" >}}.

Footnotes

I have more [^1] to say.

[^1]: Footnote example.

I have more ¹ to say.

Figures

To cross-reference a figure, provide it with an ID, for example: {{< figure src="image.jpg" id="wowchemy" >}}.

The figure can now be cross-referenced with a link in the form [A Figure](#figure-wowchemy).

Tags and Categories

Use {{< list_tags >}} to provide a list of linked tags or {{< list_categories >}} to provide a list of linked categories.

Call-to-Action Buttons

Create buttons and call-to-actions (CTA) with the CTA shortcode (new in v5.0.0.beta.1).

Example CTA button:

{{< cta cta_text="Do something" cta_link="/" cta_new_tab="false" >}}

Example CTA button with a link to an alternate action:

{{< cta cta_text="Do something" cta_link="/" cta_new_tab="false" cta_alt_text="Alternative action" cta_alt_link="/" cta_alt_new_tab="false" >}}

Mention a user

To mention someone, type {{% mention "username" %}} where username corresponds to a user account in Wowchemy.

Requires Wowchemy v4.6+.

List child pages

To list child pages, such as to list book sections from a book chapter, use {{< list_children >}}.

Images

Single image

Images may be added to a page by either placing them in your assets/media/ media library or in your page’s folder, and then referencing them using one of the following notations.

Figures are themeable according to light/dark mode and can also be cross-referenced.

A figure from your page’s folder or your assets/media/ media library:

![screen reader text](image.jpg "caption")

For more customizable figures, we can use the built-in Figure shortcode rather than the Markdown figure syntax above.

A numbered figure with a caption:

{{< figure src="image.jpg" caption="A caption" numbered="true" >}}

Using light/dark mode? Did you know that you can create dynamically themed light/dark images?

To dynamically theme images according to the user’s light or dark theme

• {{< figure src="image.jpg" caption="test" theme="light" >}} inverts image when browsing in dark mode
• {{< figure src="image.jpg" caption="test" theme="dark" >}} inverts image when browsing in light mode

Alternatively, paste a themeable inline SVG image in the form <svg fill="currentColor">...</svg> directly into your Markdown.

Image gallery

To add an image gallery to a page:

1. Create a photo album folder in assets/media/albums/
   • Or, prior to v5.3, create the album folder within your page’s folder instead
   • Album names must be lowercase due to a Hugo bug - consider up-voting the bug with a 👍
2. Add images to your album folder
3. Paste {{< gallery album="<ALBUM-FOLDER>" >}} where you would like the gallery to appear in the page content, changing the album parameter to match the name of your album folder

Optionally, to add captions for your images, add the following instances to the end of your page’s front matter:

gallery_item:
- album: <ALBUM FOLDER>
  image: <IMAGE 1 NAME>.jpg
  caption: Write your image 1 caption here
- album: <ALBUM FOLDER>
  image: <IMAGE 2 NAME>.jpg
  caption: Write your image 2 caption here

Inline image

Wowchemy enables you to use a wide range of inline images (aka icons) from Font Awesome and Academicons in addition to emojis. There is also an issue open to add support for custom images.

Here are some examples using the icon shortcode to render icons:

{{< icon name="terminal" pack="fas" >}} Terminal  
{{< icon name="python" pack="fab" >}} Python  
{{< icon name="r-project" pack="fab" >}} R

renders as

Terminal
Python
R

Optionally, left and right padding can be added to an icon using the padding_left="3" and padding_right="3" options, respectively.

Emojis

An emoji can be inserted using either an emoji keyboard or by typing the name of the emoji.

Don’t have an emoji keyboard?

Copy and paste emoji names from the Emoji cheat sheet. The following serves as an example, but remember to remove the added spaces between each emoji name and surrounding colons:

I : heart : Wowchemy : smile :

I ❤️ Wowchemy 😄

Twitter

Embed a feed

Design your timeline on Twitter and paste it into a Markdown page.

Embed a single tweet

To include a single tweet, pass the tweet’s ID from the tweet’s URL as parameter to the shortcode:

{{< tweet 666616452582129664 >}}

Callouts

Wowchemy supports a Markdown extension for callouts, also referred to as alerts or asides.

Callouts are a useful feature to draw attention to important or related content such as notes, hints, or warnings in your articles. They are especially handy when writing educational tutorial-style articles or documentation.

A callout can be created by using the Callout shortcode below. (For older Wowchemy versions prior to v5, replace callout in the examples below with alert.)

Wowchemy comes built-in with a few different styles of callouts.

The paragraph will render as a callout with the default note style:

{{% callout note %}}
A Markdown callout is useful for displaying notices, hints, or definitions to your readers.
{{% /callout %}}

This will display the following note block:

Alternatively, a warning can be displayed to the reader using the warning option:

{{% callout warning %}}
Here's some important information...
{{% /callout %}}

This will display the following warning notice to the reader:

Audio

You can add a podcast or music to a page by placing the MP3 file in the page’s folder and then referencing the audio file using the audio shortcode:

{{< audio src="markvard.mp3" >}}

Videos

The following kinds of video may be added to a page.

Local video file

Videos may be added to a page by either placing them in your static/media/ media library or in your page’s folder, and then referencing them using one of the following notations.

A video from your static/media/ media library:

{{< video library="true" src="my_video.mp4" controls="yes" >}}

A video within a page’s folder (e.g. content/post/hello/):

{{< video src="my_video.mp4" controls="yes" >}}

Youtube:

{{< youtube w7Ft2ymGmfc >}}

Vimeo:

{{< vimeo 146022717 >}}

Charts

Wowchemy supports the popular Plotly chart format.

Save your Plotly JSON in your page folder, for example chart.json, and then add the {{< chart data="chart" >}} shortcode where you would like the chart to appear.

Demo:

You might also find the Plotly JSON Editor useful.

The chart shortcode requires Wowchemy v5+.

Embed Documents

The following kinds of document may be embedded into a page.

To embed Google Documents (e.g. slide deck), click File > Publish to web > Embed in Google Docs and copy the URL within the displayed src="..." attribute. Then paste the URL in the form:

{{< gdocs src="https://docs.google.com/..." >}}

Diagrams

Wowchemy supports a Markdown extension for diagrams. You can enable this feature by toggling the diagram option in your config/_default/params.yaml file or by adding diagram: true to your page front matter. Then insert your Mermaid diagram syntax within a mermaid code block as seen below and that’s it.

An example flowchart:

```mermaid
graph TD;
  A-->B;
  A-->C;
  B-->D;
  C-->D;
```

renders as

graph TD;
  A-->B;
  A-->C;
  B-->D;
  C-->D;

An example sequence diagram:

```mermaid
sequenceDiagram
  participant Alice
  participant Bob
  Alice->John: Hello John, how are you?
  loop Healthcheck
      John->John: Fight against hypochondria
  end
  Note right of John: Rational thoughts <br/>prevail...
  John-->Alice: Great!
  John->Bob: How about you?
  Bob-->John: Jolly good!
```

renders as

sequenceDiagram
  participant Alice
  participant Bob
  Alice->John: Hello John, how are you?
  loop Healthcheck
      John->John: Fight against hypochondria
  end
  Note right of John: Rational thoughts <br/>prevail...
  John-->Alice: Great!
  John->Bob: How about you?
  Bob-->John: Jolly good!

An example Gantt diagram:

```mermaid
gantt
  dateFormat  YYYY-MM-DD
  section Section
  A task           :a1, 2014-01-01, 30d
  Another task     :after a1  , 20d
  section Another
  Task in sec      :2014-01-12  , 12d
  another task      : 24d
```

renders as

gantt
  dateFormat  YYYY-MM-DD
  section Section
  A task           :a1, 2014-01-01, 30d
  Another task     :after a1  , 20d
  section Another
  Task in sec      :2014-01-12  , 12d
  another task      : 24d

Advanced diagrams

More advanced diagrams can be created in the open source draw.io editor. The editor has support for almost any type of diagram, from simple to complex. A diagram can be easily embedded in Wowchemy by choosing File > Embed > SVG in the draw.io editor and pasting the generated code into your page.

Alternatively, a diagram can be exported as an image from any drawing software, or a document/slide containing a diagram can be embedded.

Code highlighting

Pass the language of the code, such as python, as a parameter after three backticks:

```python
# Example of code highlighting
input_string_var = input("Enter some data: ")
print("You entered: {}".format(input_string_var))
```

Result:

# Example of code highlighting
input_string_var = input("Enter some data: ")
print("You entered: {}".format(input_string_var))

Highlighting options

The Wowchemy integrates with HighlightJS for source code highlighting, the powerful technology behind some of the most popular tech sites such as StackOverflow.

Configuration options are supported that allow finer-grained control over HighlightJS.

The following table lists the supported options for configuring highlight.js, along with their expected type and a short description. A “yes” in the config.yaml column means the value can be set globally in params.yaml, and a “yes” in the front matter column means that the value can be set locally in a particular page’s front matter.

Option highlight

The highlight option allows enabling or disabling the inclusion of highlight.js, either globally or for a particular page. If the option is unset, it has the same effect as if you had specified highlight = true. That is, every page will be parsed by HighlightJS.

If you’d like to only include highlight.js files on pages that actually require source code highlighting, you can set highlight = false in params.yaml, and then override it by setting highlight: true in the front matter of any pages that require source code highlighting. Conversely, you could enable highlighting globally, and disable it locally for pages that do not require it.

Option highlight_languages

The highlight_languages option allows you to specify additional languages that are supported by HighlightJS, but are not considered “common” and therefore are not supported by default. For example, if you want source code highlighting for R and Python in all pages, set highlight_languages = ["r", "python"] in params.yaml.

If the highlight_languages option is set, then the corresponding javascript files will be served from the cdnjs server. To see a list of available languages, visit the cdnjs page and search for links with the word “languages”.

The highlight_languages option provides an easy and convenient way to include support for additional languages to be severed from a CDN. If serving unmodified files from cdnjs doesn’t meet your needs, you can include javascript files for additional language support via one of the methods described in the customization guide.

Option highlight_style

The highlight_style option allows you to select an alternate css style for highlighted code. For example, if you wanted to use the solarized-dark style, you could set highlight_style = "solarized-dark" in params.yaml.

If the highlight_style option is unset, the default is to use the file /css/highlight.min.css, either the one provided by the Wowchemy theme, or else the one in your local static directory. The /css/highlight.min.css file provided by Wowchemy is equivalent to the github style from highlight.js.

If the highlight_style option is set, then /css/highlight.min.css is ignored, and the corresponding css file will be served from the cdnjs server. To see a list of available styles, visit the cdnjs page and search for links with the word “styles”.

See the highlight.js demo page for examples of available styles.

The highlight_style option is only recognized when set in params.yaml. Setting highlight_style in your page’s preamble has no effect.

Jupyter Notebook

View the guide to blogging with Jupyter Notebooks.

GitHub gist

{{< gist USERNAME GIST-ID  >}}

$\rm \LaTeX$ math

Wowchemy supports a Markdown extension for $\LaTeX$ math. You can enable this feature by toggling the math option in your config/_default/params.yaml file.

To render inline or block math, wrap your LaTeX math with $...$ or $$...$$, respectively.

Example math block:

$$\gamma_{n} = \frac{ 
\left | \left (\mathbf x_{n} - \mathbf x_{n-1} \right )^T 
\left [\nabla F (\mathbf x_{n}) - \nabla F (\mathbf x_{n-1}) \right ] \right |}
{\left \|\nabla F(\mathbf{x}_{n}) - \nabla F(\mathbf{x}_{n-1}) \right \|^2}$$

renders as

$$\gamma_{n} = \frac{ \left | \left (\mathbf x_{n} - \mathbf x_{n-1} \right )^T \left [\nabla F (\mathbf x_{n}) - \nabla F (\mathbf x_{n-1}) \right ] \right |}{\left |\nabla F(\mathbf{x}_{n}) - \nabla F(\mathbf{x}_{n-1}) \right |^2}$$

Example inline math $\nabla F(\mathbf{x}_{n})$ renders as $\nabla F(\mathbf{x}_{n})$.

Example multi-line math using the \\\\ math linebreak:

$$f(k;p_{0}^{*}) = \begin{cases}p_{0}^{*} & \text{if }k=1, \\\\
1-p_{0}^{*} & \text{if }k=0.\end{cases}$$

renders as

$$f(k;p_{0}^{*}) = \begin{cases}p_{0}^{*} & \text{if }k=1, \\
1-p_{0}^{*} & \text{if }k=0.\end{cases}$$

Math in front matter

Math is primarily intended for use within the page body, but can also be added to page front matter variables such as a publication abstract with some additional checks.

As Hugo and Wowchemy can attempt to parse YAML, Markdown, and LaTeX content in the front matter, Markdown special characters need to be escaped in any math within the front matter fields by using a backslash to prevent the math being parsed as Markdown. The following tips may help:

• escape each LaTeX backslash (\) with an extra backslash, yielding \\
• escape each LaTeX underscore (_) with two backslashes, yielding \\_

Hence, abstract: "${O(d_{\max})}$" becomes abstract: "${O(d\\_{\\max})}$".

Subscripts & superscripts

Subscripts and superscripts can be written direct from a (unicode) keyboard or pasted from a reference.

Alternatively, you can enable math in params.yaml and use the Latex notation, for example $^2$.

Table

Code:

| Command           | Description                    |
| ------------------| ------------------------------ |
| `hugo`            | Build your website.            |
| `hugo serve -w`   | View your website.             |

Result: