From a look at the source code, it does not look like the plugin provides this option in any of two operating modes:
1.) Draw labels using the canvas - there is no way to set the color (only the family and font size). If you prefer adding JavaScript, the color won't be too complicated. (You are probably using this option as it explains why your CSS is not working.)
2.) Draw tags using the HTML DIV. This is what your linked example does. In it, the author indicates the color through the built-in CSS tag. How would I do it, though keep it all together after your plot rings:
$('.yaxisLabel').css('color','red'); $('.y2axisLabel').css('color','orange'); $('.y3axisLabel').css('color','green'); $('.y4axisLabel').css('color','purple');
An example is here .
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