Icons in Phoca Cart can be displayed using font or SVG. This can be set in Phoca Cart options. If you select the option to display icons using SVG, you can find their definition here:
- media/com_phocacart/images/svg-definitions.svg
Such a file can be copied to your active template folder and modified to your liking:
- media/templates/site/your_active_template/images/com_phocacart/svg-definitions.svg
By keeping the modified file in the active template folder, it will not be overwritten when Phoca Cart is updated.