Looking to make category pages full width? There are many posts online that tell you to edit core WooCommerce files. This is not the best practice as there are regular updates to the WooCommerce plugin. When you update the plugin, it will revert back to the page with the sidebar.

Please add this CSS code into Divi > Theme Options > General > Custom CSS field.

#left-area {
padding-right: 0 !important;
width: 100%;
}
#sidebar {
display: none;
}
#main-content .container::before {
display: none;
}