.banner-tema {
  background-image: linear-gradient(
      to right,
      rgba(0, 0, 0, 0.9),
      60%,
      transparent 100%
    ),
    linear-gradient(to left, rgba(255, 255, 255, 0.4), 30%, transparent 100%),
    url(../img/capa.jpg);
  background-repeat: no-repeat;
  background-position: center;
  background-size: cover;
}