以下是可行的解决方案（主题名为“zoran”）：

//1. Step (Create Customizer section, setting, control)

//In functions.php include or directly put code that goes something like this:



function zoran_customize_register( $wp_customize ) {
$wp_customize->add_section( \'zoran_sekcija\', array(
    \'title\'          => __( \'Zoran\', \'zoran\' ),
    \'priority\'       => 35,
) );
$wp_customize->add_setting( \'zoran_postavka\', array(
    \'default\'        => \'container\',
    \'type\' => \'theme_mod\',
    \'capability\' => \'edit_theme_options\',
) );

$wp_customize->add_control(\'zoran_control\', array(
    \'label\'   => \'Container\',
    \'section\' => \'zoran_sekcija\',
    \'settings\'   => \'zoran_postavka\',
    \'type\' => \'radio\',
    \'choices\' => array(
        \'container\' => \'Fluid\',
        \'container-fluid\' => \'Fixed\', 
    ),
) );


}
add_action( \'customize_register\', \'zoran_customize_register\' );

 //2. Step (Create javascript to manipulate class container)

 //In functions.php include or type:

function zoran_customize_js()
{
?>
     <script>
         div = document.getElementsByClassName("container");
         div[0].classList.toggle(<?php echo "\'" . get_theme_mod(\'zoran_postavka\', \'container\') . "\'"; ?>);


     </script>
<?php
}
add_action( \'wp_footer\', \'zoran_customize_js\');