Move NextGEN Gallery Custom CSS using the Customizer
NextGEN Gallery has long offered a way for users to provide custom styles using CSS for their displayed galleries:. The Custom Styles feature in NextGEN Gallery is deprecated as of version 3.5.0 https://www.imagely.com/docs/custom-s...
As of WordPress 4.7, the Customizer includes the ability to use Custom CSS to style elements behind what your selected theme does. This is a great option as its out-of-the-box with WordPress, and the method we'd recommend to most.