Change Aspect Ratio of a specific grid layout gallery page in Brine

Is there a way through CSS to change the Aspect Ratio for a specific grid style layout gallery page in my Brine template? Important to note that I have multiple grid layout gallery pages on my site, and do not want to change all of them across the board, but rather use CSS to target a specific gallery only, and leave the others untouched through the site styles settings. Appreciate any assistance that can be offered here. Thanks!