https://devdocs.magento.com/guides/v2.4/frontend-dev-guide/layouts/layout-overview.html
https://vi-magentobssthemes.com/layout-block-template-trong-magento-2/https://vi-magento.com/layout-trong-magento-2blog/magento-theme-layout/
Exercise:
In product detail, change price of product to “red” color
In product detail, add category information before add to cart button
Add form customer login to all magento frontend page, process to login.
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