https://codex.wordpress.org/Plugin_API/Filter_Reference/nav_menu_css_class


http://hookr.io/filters/nav_menu_item_id/

function remove_class( $classes, $item, $args, $depth )
{
$classes = array();
if ($item->current == true) {
$classes[] = 'current';
}
return $classes;
}add_filter( 'nav_menu_css_class', 'remove_class', 10, 4 );
function remove_id( $id, $item, $args, $depth ) {
return  $id = '';
};
add_filter( 'nav_menu_item_id', 'remove_id', 10, 4 );
functions.php
ソースコード装飾ならGoogle code prettify