bad showing of client caousel on mobile

Hello
there is a way for have a good showing of client carousel on mobile?
i have try with this that i have found on forum but is the same

@media handheld, only screen and (max-width: 767px) {
.hb-client-list li { width:auto !important; }
}

(i have try in css option like now and in child style.css)

regards
francesco