* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

body {
  font-family: Arial, sans-serif;
  background: #f4f4f4;
  color: #333;
}

header {
  background: #2c3e50;
  color: white;
  text-align: center;
  padding: 20px;
}

header p {
  opacity: 0.8;
}

.cards {
  display: grid;
  grid-template-columns: 1fr;
  gap: 20px;
  padding: 20px;
}

.card {
  background: white;
  padding: 20px;
  border-radius: 12px;
  box-shadow: 0 4px 10px rgba(0,0,0,0.1);
  text-align: center;
}

.card h2 {
  margin-bottom: 10px;
}

.card p {
  margin-bottom: 15px;
}

button {
  background: #0070f3;
  color: white;
  border: none;
  padding: 10px 15px;
  border-radius: 8px;
  cursor: pointer;
}

button:hover {
  background: #005ad1;
}

footer {
  text-align: center;
  padding: 15px;
  font-size: 14px;
}

/* Responsivo */
@media (min-width: 768px) {
  .cards {
    grid-template-columns: repeat(3, 1fr);
  }
}