:root {
  --violeta: #6425a8;
  --violeta-oscuro: #30134e;
  --fondo: #f5f1fa;
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  min-height: 100vh;
  font-family: Arial, Helvetica, sans-serif;
  background: linear-gradient(135deg, #f5f1fa, #e8dcf5);
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 24px;
}

.contenedor {
  width: 100%;
  max-width: 460px;
}

.tarjeta {
  background: #fff;
  border-radius: 20px;
  padding: 38px;
  box-shadow: 0 12px 40px rgba(48, 19, 78, 0.12);
}

.marca {
  text-align: center;
  color: var(--violeta);
  font-size: 20px;
  font-weight: bold;
  margin-bottom: 28px;
}

h1 {
  font-size: 26px;
  color: var(--violeta-oscuro);
  text-align: center;
  margin: 0 0 16px;
}

.introduccion {
  color: #666;
  text-align: center;
  line-height: 1.6;
  margin-bottom: 30px;
}

label {
  display: block;
  font-weight: bold;
  font-size: 14px;
  margin: 18px 0 8px;
  color: #333;
}

input {
  width: 100%;
  padding: 14px;
  border: 1px solid #d8cde5;
  border-radius: 10px;
  font-size: 15px;
}

input:focus {
  outline: 2px solid var(--violeta);
  border-color: transparent;
}

button {
  width: 100%;
  padding: 14px;
  border: 0;
  border-radius: 10px;
  background: var(--violeta);
  color: white;
  font-size: 15px;
  font-weight: bold;
  cursor: pointer;
}

button:hover {
  background: #4d1b85;
}

button:disabled {
  opacity: 0.6;
  cursor: not-allowed;
}

#btnRegistro {
  margin-top: 26px;
}

#mensaje {
  text-align: center;
  line-height: 1.5;
  font-size: 14px;
}

.acceso {
  margin-top: 25px;
  padding-top: 24px;
  border-top: 1px solid #eee;
  text-align: center;
  color: #666;
  font-size: 14px;
}

#btnActivar {
  margin-top: 14px;
  background: #eee6f7;
  color: var(--violeta-oscuro);
}

#btnActivar:hover {
  background: #dfcff0;
}

@media (max-width: 480px) {
  .tarjeta {
    padding: 26px 22px;
  }

  h1 {
    font-size: 23px;
  }
}