Highlight active page number in Journal Gallery Style

You can highlight the number of the active page in the journal gallery style by changing its colour.

I have changed the active page number to PINK colour using this code.

.sm-button-skin-submit.sm-button-nochrome>.sm-button-label{
  color: #fb9aa0 !important;
}

You can change the colour HEX number to any colour of your choice.  Where to add this code?  Just add a CSS content block to the ALL GALLERIES section on your site and paste the above code to it.