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+# Creating a Custom Theme in Chamilo LMS
+
+This guide explains how to properly create your own theme for Chamilo.
+
+## Folder Structure
+
+CSS files must be placed in both locations to work correctly (as of version 1.9+):
+
+1. `app/Resources/public/css/themes/{your_theme}/`
+2. `web/css/{your_theme}/`
+
+> Replace `{your_theme}` with your theme name, in lowercase.
+
+## Naming Rules
+- CSS files **must be lowercase** and use the `.css` extension.
+- Example: `default.css`, `learnpath.css`
+
+## Notes
+Currently, Chamilo duplicates CSS files in both locations, but one location may be removed in future versions.  
+Refer to the [Chamilo Developer Documentation](https://docs.chamilo.org/en/) for future updates.