CODE EXAMPLE FOR PHP

wp css deregister

// After finding the stylesheet handle, 
// you can deregister it by adding this code to your theme’s functions.php
add_action( 'wp_print_styles', 'my_deregister_styles', 100 );
function my_deregister_styles() {
wp_deregister_style( 'gdwpm_styles-css' );
wp_deregister_style( 'bfa-font-awesome-css' );
wp_deregister_style( 'some-other-stylesheet-handle' );
}