// Create widget background color setting
	$wp_customize->add_setting( 'widget_color', array(
		'default' => '#ff0000',
		'type' => 'theme_mod',
		'sanitize_callback' => 'sanitize_hex_color',
		'transport' => 'postMessage',
	));

	// Add widget background color control
	$wp_customize->add_control(
		new WP_Customize_Color_Control(
			$wp_customize,
			'widget_color', array(
				'label' => __( 'Widget Background Color', 'asuna' ),
				'section' => 'colors',
			)
		)
	);

/** Insert Customizer CSS when user selects a widget color **/

function asuna_customizer_css_widget() {
	$widget_color = get_theme_mod('widget_color');

	?>
<style type="text/css">
	#secondary {
		background-color: <?php echo $widget_color; ?>
	}
</style>
	<?php
}
add_action( 'wp_footer', 'asuna_customizer_css_widget' );