JPhotolio is support child theme. Can you help me to provide me the url of your site, so i can check it directly on my side.
Also, you can put your additional css code on JPhotolio Dashboard. You can go to JPhotolio Dashboard > Style / Color Option > Additional.
Or if you’re using WordPress 4.7 or higher, you can put your additional css code on Customizer. No need to worry about losing your code after theme update.