Add the codes below to your theme’s function.php file :
add_action(‘admin_head’, ‘adminbarhide’);
function adminbarhide() {
define(‘BP_DISABLE_ADMIN_BAR’, true);
}
then go to wp-content/your-theme-directory/_inc/css/adminbar.css and change “padding-top: 25px” on second line to “padding-top: 0px” ,
this code will remove admin bar only from your dashboard, and css code will hide white space after removing admin bar.
after all I’m sorry about my bad English if there was some wrong spelling.