Overwrite Magento Core using a Module | Tom Lankhorst
The layout of Magento’s information, warning and error messages cannot be easily changed using layout and template files. The HTML generation is done from a Block PHP class (Mage_Core_Block_Messages). It is a very bad idea to overwrite any core element of Magento. Instead we are going to extend this core-block by creating a separate module. Messages are now Bootstrap compatible My goal was to make the messages compliant with Twitter Bootstrap alerts but the following technique can be used for about anything.
Overwrite Magento Core using a Module | Tom Lankhorst
The layout of Magento’s information, warning and error messages cannot be easily changed using layout and template files. The HTML generation is done from a Block PHP class (Mage_Core_Block_Messages). It is a very bad idea to overwrite any core element of Magento. Instead we are going to extend this core-block by creating a separate module. Messages are now Bootstrap compatible My goal was to make the messages compliant with Twitter Bootstrap alerts but the following technique can be used for about anything.
https://tomlankhorst.nl/creating-module-to-overwrite-magento-core/