sin.sfx on "[Plugin: Polylang] specific style css ( rtl.css)"

Morning,
I tried that, but the rtl.css didn't loaded !
i found a solution to load it, i used condition with is_rtl()

if ( is_rtl() ) {
wp_enqueue_style('rtl', CSSPATH . 'rtl.css');
}

Im still confused, how to do it on the right way ?

Thanks again Chouby