body {
  margin: 0;
  font-family: "Segoe UI", sans-serif;
  background-color: #0b0b0f;
  color: #f0f0f0;
}

.hero {
  text-align: center;
  padding: 3rem 1rem;
  background: radial-gradient(ellipse at center, #111 0%, #000 100%);
}

.language-switch {
  position: absolute;
  top: 20px;
  right: 20px;
}

.language-switch button {
  background: none;
  border: none;
  font-size: 1.5rem;
  cursor: pointer;
}

.cta-button {
  display: inline-block;
  margin-top: 1rem;
  padding: 0.8rem 1.5rem;
  background: #00bcd4;
  color: #000;
  text-decoration: none;
  border-radius: 5px;
  font-weight: bold;
}

.books {
  padding: 2rem;
  text-align: center;
}

.book-row {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 2rem;
  min-height: 200px;
}

.book img {
  width: 180px;
  height: auto;
  box-shadow: 0 4px 12px rgba(0, 255, 255, 0.2);
}

.book-title {
  font-weight: bold;
  margin-top: 18.5rem;
}

.buy-button {
  margin-top: 0.5rem;
  display: inline-block;
  color: #0ff;
  text-decoration: underline;
}

.coming-soon {
  display: block;
  margin-top: 0.5rem;
  color: #999;
}

.about {
  padding: 2rem;
  text-align: center;
  max-width: 700px;
  margin: auto;
}

footer {
  padding: 1rem;
  text-align: center;
  background-color: #111;
  font-size: 0.9rem;
  color: #777;
}

.book {
  position: relative;
  width: 180px;  /* ancho fijo para ejemplo */
  height: auto;  /* ajustará el alto automáticamente (o fija altura proporcional) */
  cursor: pointer;
  overflow: visible;
}

.book img {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: auto;
  transition: opacity 0.3s ease-in-out, transform 0.3s ease-in-out;
}

/* La portada frontal (versión “plana”) visible por defecto */
.hover-3d .front {
  opacity: 1;
  transform: scale(1);
  z-index: 1;
  display: block;
}

/* La versión 3D / con lomo oculta al inicio */
.hover-3d .back {
  opacity: 0;
  transform: scale(0.9) translateY(10px); /* un poco desplazado para efecto */
  z-index: 0;
  display: none;
}

/* Al hacer hover */
.hover-3d:hover .front {
  opacity: 0;
  transform: scale(1.1);
  display: none;
}

.hover-3d:hover .back {
  opacity: 1;
  transform: scale(1) translateY(0);
  z-index: 2;
  display: block;
}