.carousel-caption-box {
  position: absolute;
  bottom: 1.5rem;
  left: 50%;
  transform: translateX(-50%);
  color: #fff;
  padding: 1.5rem 2rem;
  border-radius: .5rem;
  max-width: 90%;
  text-align: center;
  backdrop-filter: blur(4px); /* suaviza el fondo */
}