In Drupal, indentation is used to format the code for better readability and maintainability. To indent code in Drupal, you can follow these general guidelines:

1. Indentation in PHP:
– Use spaces for indentation rather than tabs, as per Drupal coding standards.
– Indent each level of code by four spaces.
– Maintain consistent indentation throughout your code.

Example:
"`php
function my_function()
"`

2. Indentation in Twig templates:
– Use two spaces for indentation in Twig templates.
– Indent each level of code by two spaces.
– Maintain consistent indentation throughout the template.

Example:
"`twig

"`

3. Indentation in CSS:
– Use two spaces for indentation in CSS files.
– Indent each level of code by two spaces.
– Maintain consistent indentation throughout the CSS rules.

Example:
"`css
.my-class
"`

4. Indentation in JavaScript:
– Use two spaces for indentation in JavaScript files.
– Indent each level of code by two spaces.
– Maintain consistent indentation throughout your JavaScript code.

Example:
"`javascript
function myFunction()
"`

Remember that consistent and clear indentation improves code readability and makes it easier to understand and maintain. Following these guidelines will help ensure that your code adheres to Drupal coding standards and best practices.