Centering Footer text: CSS does not work

Dear Travelify creators, we are super happy to have been using your theme for many years now! We have created with it and love it very much. However, we recently added an extra footer text (naming the source of our background picture) and this text is not centered.

We have already tried adding this code to Custom CSS:

body #site-generator .copyright {
float: none;
text-align: center;

However, this does not seem to work. Do you maybe have another solution? Many thanks in advance!

The Hennali Henna team