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/**
 * Change the logo on login screen
 */
function modify_logo() {     
	$logo_style = '<style type="text/css">';     
	$logo_style .= 'h1 a {background-image: url(' . get_template_directory_uri() . '/images/logo.png) !important;}';     
	$logo_style .= '</style>';     
	echo $logo_style; 
} 
	
add_action('login_head', 'modify_logo');