Change font color, size, font

I’d like to change the font color, font size, and ideally the font in my testimonials. I’ve tried various ways of configuring .testimonials-widget-testimonial with no luck. I have been able to change the color of the quote marks with this css

.testimonials-widget-testimonial blockquote {
color: blue;
}

but haven’t been able to change the font color or size.

Any help appreciated!

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