Remove post in box from activity post form

// Remove post in box from activity wire other user posting activity post form
function remove_activity_post_in_box() {
	?>
<style type="text/css">
body.activity.bp-user #whats-new-post-in-box{ display:none;}


</style>
<?php
}
add_action ('bp_head', 'remove_activity_post_in_box');