Where are you editing the nivo-slider’s CSS? Since it is now supporting themes, there is a theme .css being loaded and a theme-themename class being added to the slider. So for example if you’re using the default theme the plugin will load
nextgen-nivoslider\themes\default\default.css
and will add the theme-default class to nivoslider. In the default.css styles are being set as following:
.theme-default .nivoSlider. {
}
Meaning it might be overriding your styles if you’re defining them elsewhere and with less selectors. Edit default.css (or another theme, depending on which one you’ve chosen) to alter the style or be more specific with your selectors. If wanted I could also add an option to disable themes altogether. I implemented them to make all the functionality of NivoSlider available.
have you tried setting the CSS as following?
#featured-image .nivoSlider {
margin: 27px auto;
max-height: 498px;
max-width: 920px;
padding: 0;
position: relative;
top: 0;
}
Since this is specific it should set the style to the nivoSlider container.