您可以简单地使插件css依赖于主题css，而子主题css依赖于插件css。

function wpdocs_custom_scripts() {

    // example theme style
    wp_enqueue_style( \'theme-style\', \'#\' );

    // Plugin css
    wp_enqueue_style( \'plugin-style\', \'#\', array( \'theme-style\' ) ); // see "theme-style" passed in $deps param,

    // Child theme css
    wp_enqueue_style( \'child-style\', \'#\', array( \'plugin-style\' ) ); // see "plugin-style" passed in $deps param,
}
add_action( \'wp_enqueue_scripts\', \'wpdocs_custom_scripts\' );

这样，它们将按以下顺序加载

<link rel=\'stylesheet\' id=\'theme-style-css\'  href=\'#\' type=\'text/css\' />
<link rel=\'stylesheet\' id=\'plugin-style-css\'  href=\'#\' type=\'text/css\' />
<link rel=\'stylesheet\' id=\'child-style-css\'  href=\'#\' type=\'text/css\' />

Another Approach:您还可以使用中的priority参数wp_enqueue_scripts. 使优先级降低，以便更早加载。像这样

function wpdocs_custom_theme_scripts() {
    // theme style
    wp_enqueue_style( \'theme-style\', \'#\' );
}
add_action( \'wp_enqueue_scripts\', \'wpdocs_custom_theme_scripts\', 9 );

function wpdocs_custom_plugin_scripts() {
    // Plugin css
    wp_enqueue_style( \'plugin-style\', \'#\' );
}

add_action( \'wp_enqueue_scripts\', \'wpdocs_custom_plugin_scripts\', 10 );

function wpdocs_custom_child_scripts() {
    // Child theme css
    wp_enqueue_style( \'child-style\', \'#\' );
}
add_action( \'wp_enqueue_scripts\', \'wpdocs_custom_child_scripts\', 11 );