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Your LimeSurvey version: 6.26
Own server hosting
Survey theme/template: fruity
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I apologize if this is a duplicate answer but I did find it asked previously but way back for V2. 
Where can I change the color for just the YES/No questions. I deal with so disabled people and the contrast between the selected and not selected answer seems almost the same on all the variations of fruity that I’ve tried. I found an answer that talked about the template.css but I don’t see it anywhere. 
i loooked through the twig files but still don’t see it. But I’m not great with CSS so please forgive me. 

How do you intend to increase the contrast, this is what I see with the fruity_twentythree theme.

  

My computer just died so I can’t send a screenshot. I tried all the “fruity” variation. I have not tried fruity_twentythree. But on the fruity it’s a color on a variation of that color. So blue when not selected and a slightly different blue (darker ) when selected. Or green with darker green. You can hardly tell when it’s selected

First, extend the theme - www.limesurvey.org/manual/New_Template_S...S3.x/en#Theme_Editor

If using the fruity/skyline-blue variation and you want to restrict this to yes/no questions, add something like this to the end of the custom.css file:


 

Awesome. Thank you so much. That’s exactly what I needed.

Ok I’m still having trouble with this. Sorry.
As long as it’s inherited, the response from tpartner works great. But how do I make the changes to each of the theme variations. I’m using fruity (extends_fruity) and let’s say sea_green is the variation.
I tried .extends_fruity/sea_green and .fruity/sea_green
the editor dislikes, the /