title: How to create sub md files with content that applies to the page md files
body: <p>I'm creating a website using Jekyll.
  so far I have four pages which are created automatically from four md files which md files are in the root of the project.</p>
  
  <pre><code>index.md
  about.md
  login.md
  register.md
  </code></pre>
  
  <p>Here is the content inside my <code>login.md file</code></p>
  
  <pre><code>---
  layout: layout-default
  title: some login title
  permalink: /login
  theme: secondary-theme 
  nav:
      menu-items:
          - type: text
            text: Don't have an account?
          - type: link
            text: SIGN UP
            class: button
            linkPath: /register
  sections:
      - type: 3
        class: form-section
        header-line-2: Login Section!
        form:
          api: http://127.0.0.1:8080/login
          submit-text: LOG IN
          form-controls:
              - label-text: EMAIL ADDRESS
                input-type: email
                input-placeholder: Enter your email
                input-name: email
              - label-text: PASSWORD
                label-link-text: Forgot password?
                label-link-path: #
                input-type: password
                input-placeholder: Enter your password
                input-name: password
  
  ---
  </code></pre>
  
  <p>What i do is iterating the sections and applying html attribute values depending on the variables inside each section. That way i can have as many sections rendered as i want on one page. And they can also be different depending on the classes and content i put in the md file.
  The problem is that if the project gets too complicated with different styles for sections and so on. I would like to separate each section content. It would be nice if i could make a folder lets say login/sections folder
  and then put md files inside and then inside login.md file include these section md files. This way the code would be much more organized.
  Is there way to do that, and is my approach actually good.</p>