A child theme lets you add custom CSS, PHP, or template changes that survive theme updates. If you plan to edit theme files, always use a child theme.
1. Check the theme download bundle — most of our themes include a ready-made child theme .zip. If yours does, upload and activate it from Appearance → Themes. 2. If there's no bundled child theme, create a folder like theme-name-child with a style.css and functions.css that reference the parent theme. Our documentation includes the exact snippet. 3. Put custom CSS in the child theme's stylesheet, and custom functions in its functions.php.
For small CSS-only tweaks you don't even need a child theme — use Appearance → Customize → Additional CSS, which is also update-safe.