Throughout this chapter we've covered more of the many different methods you can use to bend Drupal themes to your will. We've covered almost everything you'll need to know to create truly awesome and sustainable themes, including how to:

  • Find the variables that are available to you in the theme layer.
  • Understand and use preprocess and process functions.
  • Use and alter contents of render arrays.
  • Theme forms with templates, theme functions, and alter hooks.
  • Manage CSS and JavaScript files in your theme.
  • Work with base and subthemes.

It's easy to become overwhelmed with Drupal's theme layer in the beginning. Just remember that your themes can be as simple or as complex as you need them or want to be. We hope that you'll take this knowledge and use it to create awesome Drupal themes, and contribute them back to the community.