.banner {
  width: 100%;
  height: 200px;
  background-size: cover;
  background-position: center;
  display: flex;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  color: #ffffff;
  text-align: center;
  padding: 20px;
  filter: brightness(1.5); 
}
.banner h1 {
  font-size: 2.5rem;
  margin-bottom: 10px;
}
.banner-somos{
  background-image: linear-gradient(rgba(0,0,0,0.5), rgba(0,0,0,0.5)), url('../images/banner1.jpg');
}
.banner-admisiones{
  background-image: linear-gradient(rgba(0,0,0,0.5), rgba(0,0,0,0.5)), url('../images/banner2.jpg');
}
.banner-niveles{
  background-image: linear-gradient(rgba(0,0,0,0.5), rgba(0,0,0,0.5)), url('../images/banner3.jpg');
}