# Configuring Icarus

The configuration of Icarus consists of two parts: theme configuration and post configuration.

# Polymorphic Link Settings

You may already notice that Icarus allows you to put icon links on the right of the navigation bar, the bottom of the profile widget, and the right side of the footer with the following format:

# Adding a Thumbnail to Your Article

You can add thumbnail images to your posts in two steps. First, make sure the thumbnail is enabled in the theme’s configuration file:

Then, provide an URL or path to the image file in the front-matter of your post:

### About thumbnail image path

The image path you put in the front-matter needs to be the relative path to the source directory of your website. For example, if you want to use the following image as a thumbnail:

You need to use the following as the image path:

Also, it is recommended that you put all the images under a dedicated asset folder that is separated from the _posts folder.

To display a Table of Contents / Catalogue (toc) widget on a post page, please first add toc: true to the front-matter of your post Markdown file:

Then, add the toc widget to the theme’s configuration file:

# Speed up Your Site with Custom CDN

Using a right CDN provider can speed up page loading process of your viewers. Icarus allows you to specify the CDN provider of third-party static libraries you want to use.

### Built-in CDN providers

Currently, you can choose between these built-in providers:

• General CDNs
• CDN.js (cdnjs)
• jsDelivr (jsdelivr)
• Unpkg (unpkg)
• Font CDNs
Sometimes you may want your sidebar’s position to stay fixed when other parts of your page scrolls. This can be done via the sticky option of the sidebar in the theme’s _config.yml. You can set any of the sidebar or even both of them to sticky.