#testimonial-container {
    height: 240px;
    width: 427px;
}
@media (min-width: 640px) {
       #testimonial-container {
        height: 360px;
        width: 640px;
    }
}

@media (min-width: 1536px) {
    #testimonial-container {
        height: 480px;
        width: 854px;
    }

}