Create a basic custom Drupal 10 theme tutorial

This tutorial will give you everything you need to create a very basic custom theme for Drupal 10. It will just show up as an available theme in Drupal and not much more.

1. Create a folder named d10_custom_theme_base inside the themes/custom/ folder of your Drupal 10 installation.

   
   core
   modules
   profiles
   sites
   themes
   --contrib
   --custom
   ----d10_custom_theme_base
   

2. Save a text file with the name d10_custom_theme_base.info.yml inside the created folder.
3. Edit the d10_custom_theme_base.info.yml file to include the following:

   
   name: D10 Custom Theme Base
   type: theme
   description: 'A Drupal 10 custom theme base.'
   core_version_requirement: '^10'
   base theme: 'false'
   regions:
       header: 'Header'
       content: 'Content'
       sidebar_first: 'Sidebar first'
       footer: 'Footer'
   

4. Congratulations! You have a custom theme.

More information

• Drupal theme folder structure
• Defining a theme with an .info.yml file
  • Required and optional items
• D10 custom theme base github repository