How do I override WordPress plugin css [closed]

Assuming you are overriding the Page Builder styles with vc-style stylesheet.

Try this..

function vc_override() {
    wp_enqueue_style( 'vc-style', get_stylesheet_directory_uri() . '/css/vc_elements-style.css', array('js_composer_front') ); //visual composer
}
add_action( 'wp_enqueue_scripts', 'vc_override', 999 );

View your site’s source to check whether your style is appearing before or after visual composer style.