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How to use Illustrator graphic styles in different color models such as RGB and CMYK tutorial. The Illustrator graphic effects on this site are stored in the RGB color model in 99% of the cases. Some of them are in CMYK (or contain both) also but I have always found those an issue with the black channel and mixing of the gradients and colors. They will work fine in a CMYK color mode / document but in some cases you may have to modify some of the settings to get a similar effect or see any effect at all.
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Another issue with the graphic styles for Illustrator CMYK - sometimes the icon for the effect looks the same as the actual result but in some cases, they definitely do not. Makes it very hard to choose an preset in the color mode, CMYK
How to fix this issue, tricky for many of the more graphic styles as they were created in RGB with a lot of different gradients and patterns which were all created in RGB and to change them quickly to CMYK is a slow slog through the the color balance settings or using the appearance panel and selecting each of the gradients that are used to build the graphic style but the required setting for each depending on the complex blending modes used may be too tricky to create anything like the RGB style.
Personally, a few tweaks with the adjust color balance is often quite useful for correcting the color (I am certain that purists would disagree) but then again, probably not going to use RGB in CMYK in the first place
select the individual items and tweak the gradients individually
use the edit menu
adjust color balance - it can be effective with some styles and is a great way of creating some subtle color changes to the styles (an alternative being the color guide feature)