Testimonial Grid - Mobile First Solution and Responsive

I could work with CSS Grid without a problem.

I'm confused with the height. I usually work with the Figma design, so when I'm working with the screen sizes that is in there, the result is properly the same, but when I change for other ones that are not the same as the file, it used to change. For example, in this project if I set the width and height of any device's screen that is in the file, it seems correct, but if I change the height size, it completely act different. Also in some screen sizes, I cannot adapt the content to be properly center vertically, it seems like there is no margin or space to be free, hope that I can understand this situation.