* {
  box-sizing: border-box;
}
body {
  margin: 0;
  padding: 0;
  font-family: 'Segoe UI', sans-serif;
  background: #0f172a;
  color: #e2e8f0;
  display: flex;
  justify-content: center;
  min-height: 100vh;
}

/* Contenedor que centra y limita el ancho máximo */
.container {
  width: 100%;
  max-width: 880px;
  margin: auto;
  padding: 2rem 1.5rem;
  display: flex;
  flex-direction: column;
  justify-content: center;
}

/* Encabezado */
header {
  text-align: center;
  margin-bottom: 2rem;
}
h1 {
  font-size: 2.8rem;
  margin-bottom: 0.5rem;
}
p {
  font-size: 1.2rem;
  margin-bottom: 1.5rem;
}
.cta-button {
  background-color: #facc15;
  color: #1f2937;
  padding: 0.75rem 1.5rem;
  text-decoration: none;
  font-weight: bold;
  border-radius: 4px;
  transition: background 0.3s ease;
}
.cta-button:hover {
  background-color: #fde047;
}

/* Secciones principales */
.features,
.concept {
  text-align: center;
  margin-bottom: 2.5rem;
}
.features h2,
.concept h2 {
  font-size: 1.75rem;
  color: #facc15;
  margin-bottom: 1rem;
}
.features ul {
  list-style: none;
  padding: 0;
}
.features li {
  margin: 0.75rem 0;
  font-weight: 500;
}
.concept p {
  margin-bottom: 1rem;
  line-height: 1.6;
  color: #cbd5e1;
}

/* Pie de página */
footer {
  text-align: center;
  font-size: 0.85rem;
  padding: 1rem 0;
  background: #1e293b;
  border-radius: 0 0 6px 6px;
}

/* Animación de aparición */
.fade-in {
  animation: fadeIn 1.8s ease-in-out;
}
@keyframes fadeIn {
  from { opacity: 0; transform: translateY(-20px); }
  to { opacity: 1; transform: translateY(0); }
}

/* Responsividad para móviles */
@media (max-width: 600px) {
  h1 {
    font-size: 2.2rem;
  }
  p, .features li, .concept p {
    font-size: 1rem;
  }
  .features h2, .concept h2 {
    font-size: 1.4rem;
  }
}