.hero {
    height: 35vh;  /* 35% of viewport height */
    background: url('/assets/images/dbk1.jpg') center/cover no-repeat;
    position: relative;
    z-index: 1;
  }
  .hero::before {
    content: "";
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.5);
    z-index: -1;
  }