--- title: Themes permalink: /docs/themes/ --- Jekyll has an extensive theme system that allows you to leverage community-maintained templates and styles to customize your site's presentation. Jekyll themes package up layouts, includes, and stylesheets in a way that can be overridden by your site's content. ## Understanding gem-based themes When you [create a new Jekyll site](/docs/quickstart) (by running the `jekyll new ` command), Jekyll installs a site that uses a gem-based theme called [Minima](https://github.com/jekyll/minima). With gem-based themes, some of the site's directories (such as the `assets`, `_layouts`, `_includes`, and `_sass` directories) are stored in the theme's gem, hidden from your immediate view. Yet all of the necessary directories will be read and processed during Jekyll's build process. In the case of Minima, you see only the following files in your Jekyll site directory: ``` ├── Gemfile ├── Gemfile.lock ├── _config.yml ├── _posts │ └── 2016-12-04-welcome-to-jekyll.markdown ├── about.md └── index.md ``` The `Gemfile` and `Gemfile.lock` files are used by Bundler to keep track of the required gems and gem versions you need to build your Jekyll site. Gem-based themes make it easy for theme developers to make updates available to anyone who has the theme gem. When there's an update, theme developers push the update to RubyGems. If you have the theme gem, you can (if you desire) run `bundle update` to update all gems in your project. Or you can run `bundle update `, replacing `` with the theme name, such as `minima`, to just update the theme gem. Any new files or updates the theme developer has made (such as to stylesheets or includes) will be pulled into your project automatically. The goal of gem-based themes is to allow you to get all the benefits of a robust, continually updated theme without having all the theme's files getting in your way and over-complicating what might be your primary focus: creating content. ## Overriding theme defaults Jekyll themes set default layouts, includes, and stylesheets. However, you can override any of the theme defaults with your own site content. For example, if your selected theme has a `page` layout, you can override the theme's layout by creating your own `page` layout in the `_layouts` directory (that is, `_layouts/page.html`). Jekyll will look first to your site's content before looking to the theme's defaults for any requested file in the following folders: - `/assets` - `/_layouts` - `/_includes` - `/_sass` Refer to your selected theme's documentation and source repository for more information on what files you can override. {: .note .info} To locate theme's files on your computer: 1. Run `bundle show` followed by the name of the theme's gem, e.g., `bundle show minima` for default Jekyll's theme. This returns the location of the gem-based theme files. For example, Minima theme's files are located in `/usr/local/lib/ruby/gems/2.3.0/gems/minima-2.1.0` on macOS. 2. Open the theme's directory in Finder or Explorer: ```shell # On MacOS open $(bundle show minima) # On Windows explorer /usr/local/lib/ruby/gems/2.3.0/gems/minima-2.1.0 ``` A Finder or Explorer window opens showing the theme's files and directories. The Minima theme gem contains these files: ``` ├── LICENSE.txt ├── README.md ├── _includes │   ├── disqus_comments.html │   ├── footer.html │   ├── google-analytics.html │   ├── head.html │   ├── header.html │   ├── icon-github.html │   ├── icon-github.svg │   ├── icon-twitter.html │   └── icon-twitter.svg ├── _layouts │   ├── default.html │   ├── home.html │   ├── page.html │   └── post.html ├── _sass │   ├── minima │   │   ├── _base.scss │   │   ├── _layout.scss │   │   └── _syntax-highlighting.scss │   └── minima.scss └── assets └── main.scss ``` With a clear understanding of the theme's files, you can now override any theme file by creating a similarly named file in your Jekyll site directory. Let's say you want to override Minima's footer. In your Jekyll site, create an `_includes` folder and add a file in it called `footer.html`. Jekyll will now use your site's `footer.html` file instead of the `footer.html` file from the Minima theme gem. ## Converting gem-based themes to regular themes Suppose you want to get rid of the gem-based theme and convert it to a regular theme, where all files are present in your Jekyll site directory, with nothing stored in the theme gem. To do this, copy the files from the theme gem's directory into your Jekyll site directory. (For example, copy them to `/myblog` if you created your Jekyll site at `/myblog`. See the previous section for details.) Then remove references to the theme gem in `Gemfile` and configuration. For example, to remove `minima`: - Open `Gemfile` and remove `gem "minima", "~> 2.0"`. - Open `_config.yml` and remove `theme: minima`. Now `bundle update` will no longer get updates for the theme gem. ## Installing a gem-based theme {#installing-a-theme} The `jekyll new ` command isn't the only way to create a new Jekyll site with a gem-based theme. You can also find gem-based themes online and incorporate them into your Jekyll project. For example, search for [jekyll theme on RubyGems](https://rubygems.org/search?utf8=%E2%9C%93&query=jekyll-theme) to find other gem-based themes. (Note that not all themes are using `jekyll-theme` as a convention in the theme name.) To install a gem-based theme: 1. Add the theme to your site's `Gemfile`: ```sh gem "jekyll-theme-awesome" ``` 2. Install the theme: ```sh bundle install ``` 3. Add the following to your site's `_config.yml` to activate the theme: ```sh theme: jekyll-theme-awesome ``` 4. Build your site: ```sh bundle exec jekyll serve ``` You can have multiple themes listed in your site's `Gemfile`, but only one theme can be selected in your site's `_config.yml`. {: .note .info } If you're publishing your Jekyll site on [GitHub Pages](https://pages.github.com/), note that GitHub Pages supports only some gem-based themes. See [Supported Themes](https://pages.github.com/themes/) in GitHub's documentation to see which themes are supported. ## Creating a gem-based theme If you're a Jekyll theme developer (rather than just a consumer of themes), you can package up your theme in RubyGems and allow users to install it through Bundler. If you're unfamiliar with creating Ruby gems, don't worry. Jekyll will help you scaffold a new theme with the `new-theme` command. Run `jekyll new-theme` with the theme name as an argument. Here is an example: ```sh jekyll new-theme jekyll-theme-awesome create /path/to/jekyll-theme-awesome/_layouts create /path/to/jekyll-theme-awesome/_includes create /path/to/jekyll-theme-awesome/_sass create /path/to/jekyll-theme-awesome/_layouts/page.html create /path/to/jekyll-theme-awesome/_layouts/post.html create /path/to/jekyll-theme-awesome/_layouts/default.html create /path/to/jekyll-theme-awesome/Gemfile create /path/to/jekyll-theme-awesome/jekyll-theme-awesome.gemspec create /path/to/jekyll-theme-awesome/README.md create /path/to/jekyll-theme-awesome/LICENSE.txt initialize /path/to/jekyll-theme-awesome/.git create /path/to/jekyll-theme-awesome/.gitignore Your new Jekyll theme, jekyll-theme-awesome, is ready for you in /path/to/jekyll-theme-awesome! For help getting started, read /path/to/jekyll-theme-awesome/README.md. ``` Add your template files in the corresponding folders. Then complete the `.gemspec` and the README files according to your needs. ### Layouts and includes Theme layouts and includes work just like they work in any Jekyll site. Place layouts in your theme's `/_layouts` folder, and place includes in your themes `/_includes` folder. For example, if your theme has a `/_layouts/page.html` file, and a page has `layout: page` in its YAML front matter, Jekyll will first look to the site's `_layouts` folder for the `page` layout, and if none exists, will use your theme's `page` layout. ### Assets Any file in `/assets` will be copied over to the user's site upon build unless they have a file with the same relative path. You can ship any kind of asset here: SCSS, an image, a webfont, etc. These files behave like pages and static files in Jekyll: - If the file has [YAML front matter](/docs/frontmatter/) at the top, it will be rendered. - If the file does not have YAML front matter, it will simply be copied over into the resulting site. This allows theme creators to ship a default `/assets/styles.scss` file which their layouts can depend on as `/assets/styles.css`. All files in `/assets` will be output into the compiled site in the `/assets` folder just as you'd expect from using Jekyll on your sites. ### Stylesheets Your theme's stylesheets should be placed in your theme's `_sass` folder, again, just as you would when authoring a Jekyll site. ``` _sass ├── jekyll-theme-awesome.scss ``` Your theme's styles can be included in the user's stylesheet using the `@import` directive. ```css {% raw %}@import "{{ site.theme }}";{% endraw %} ``` ### Documenting your theme Your theme should include a `/README.md` file, which explains how site authors can install and use your theme. What layouts are included? What includes? Do they need to add anything special to their site's configuration file? ### Adding a screenshot Themes are visual. Show users what your theme looks like by including a screenshot as `/screenshot.png` within your theme's repository where it can be retrieved programatically. You can also include this screenshot within your theme's documentation. ### Previewing your theme To preview your theme as you're authoring it, it may be helpful to add dummy content in, for example, `/index.html` and `/page.html` files. This will allow you to use the `jekyll build` and `jekyll serve` commands to preview your theme, just as you'd preview a Jekyll site. If you do preview your theme locally, be sure to add `/_site` to your theme's `.gitignore` file to prevent the compiled site from also being included when you distribute your theme. {: .info .note} ### Publishing your theme Themes are published via [RubyGems.org](https://rubygems.org). You will need a RubyGems account, which you can [create for free](https://rubygems.org/sign_up). 1. First, you need to have it in a git repository: ```sh git init # Only the first time git add -A git commit -m "Init commit" ``` 2. Next, package your theme, by running the following command, replacing `jekyll-theme-awesome` with the name of your theme: ```sh gem build jekyll-theme-awesome.gemspec ``` 3. Finally, push your packaged theme up to the RubyGems service, by running the following command, again replacing `jekyll-theme-awesome` with the name of your theme: ```sh gem push jekyll-theme-awesome-*.gem ``` 4. To release a new version of your theme, update the version number in the gemspec file, ( `jekyll-theme-awesome.gemspec` in this example ), and then repeat Steps 1 - 3 above. We recommend that you follow [Semantic Versioning](http://semver.org/) while bumping your theme-version.