how to align right the title?

Hi,
Great plugin – thank you!
How can I align right (or make RTL) the “Chat with us” title?
I tried to add a text-align in style.css but it doesn’t work:

#livelychatsupport-chatbox.offline .cta_online_text {
  display: none;
  text-align: right;
}

See https://smallsigns.net/
Regards,
Ugo

https://www.ads-software.com/plugins/lively-chat-support/