Auto Generated CSS file do not removed

[allensph]

The UPLOAD option generated css file in uploads directory,
but when I remove image from customizer, the css file still exist.
How can I remove / change css bind on option change ?

$titan = TitanFramework::getInstance( 'my-theme-id' );

$imageID = $titan->getOption( 'my_upload_option' );
$imageSrc = $imageID; // For the default value

if ( is_numeric( $imageID ) ) {
	$imageAttachment = wp_get_attachment_image_src( $imageID );
	$imageSrc = $imageAttachment[0];
}

$section = $titan->createThemeCustomizerSection( array(
	'id' => 'background_image',
) );

$section->createOption( array(
	'name' => 'My Upload Option',
	'id' => 'my_upload_option',
	'type' => 'upload',
	'desc' => 'Upload your image',
	'livepreview' => '$("header").css("background",value)'
	'css' => 'header { background: value }'
) );