You can style the testimonial shortcode from here use your own color schema, change font size, color, weight etc..
4.1) Parent Class: you can set a parent class for each shortcode.
4.2) Color Schema: You can set Primary color, Container background and Item background color.
4.3) Button Color: You can set button background & Text color.
4.4) Gutter / Padding: [PRO] Set testimonial item to item padding.
4.5) Overlay Style: Set overlay color, opacity & padding.
4.6) Image Border Style: [PRO] set border px, color and style.
4.7) Author Name: Set Author Name color, Font size, Weight & Alignment.
4.8) Author Bio: Set Author Bio color, Font size, Weight & Alignment.
4.9) Rating: Set Rating color, Font size, Weight & Alignment.
4.10) Social: [PRO] Set Social color, Font size, Weight & Alignment.
4.11) Testimonial Style: Set color, Font size, font style, weight & Alignment.
