body, html {
  margin: 0;
  padding: 0;
  font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
  scroll-behavior: smooth;
}

.seccion {
  position: relative;
  width: 100%;
  padding: 80px 20px;
  text-align: center;
  color: white;
}

.parallax {
  background-attachment: fixed;
  background-position: center;
  background-repeat: no-repeat;
  background-size: cover;
}

#fondo1 { background-image: url('fondo1.jpg'); }
#fondo2 { background-image: url('fondo2.jpg'); }
#fondo3 { background-image: url('fondo3.jpg'); }
#fondo4 { background-image: url('fondo4.jpg'); }

.normal {
  background: #222;
  color: #eee;
}

.contenido {
  background: rgba(0, 0, 0, 0.6);
  padding: 40px;
  border-radius: 10px;
  display: inline-block;
  max-width: 600px;
  margin: auto;
}