WordPress主题开发：如何在外观-自定义中添加主题主色调设置项

function mytheme_customize_register( $wp_customize ) {
    // 添加分组：主题配色
    $wp_customize->add_section( 'mytheme_color_scheme', array(
        'title'    => __( '主题配色', 'mytheme' ),
        'priority' => 30,
    ) );

    // 添加设置项：主色调
    $wp_customize->add_setting( 'primary_color', array(
        'default'           => '#0088cc',
        'sanitize_callback' => 'sanitize_hex_color',
        'transport'         => 'refresh',
    ) );

    // 添加控件：颜色选择器
    $wp_customize->add_control( new WP_Customize_Color_Control(
        $wp_customize,
        'primary_color',
        array(
            'label'    => __( '主题主色调', 'mytheme' ),
            'section'  => 'mytheme_color_scheme',
            'settings' => 'primary_color',
        )
    ) );
}
add_action( 'customize_register', 'mytheme_customize_register' );

<style type="text/css">
    :root {
        --primary-color: <?php echo esc_attr( get_theme_mod( 'primary_color', '#0088cc' ) ); ?>;
    }
</style>

.button {
    background-color: var(--primary-color);
}