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

body {
  background: #0f0f0f;
  min-height: 100vh;
  display: flex;
  justify-content: center;
  align-items: center;
  font-family: 'Segoe UI', system-ui, sans-serif;
}

.grilla {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 16px;
  padding: 2rem;
  max-width: 700px;
  width: 100%;
}

.tarjeta {
  background: #1a1a1a;
  color: #e0e0e0;
  border: 1px solid #2a2a2a;
  border-radius: 10px;
  padding: 2.5rem 1rem;
  font-size: 0.95rem;
  letter-spacing: 0.03em;
  cursor: pointer;
  transition: background 0.2s, border-color 0.2s, color 0.2s;
}

.tarjeta:hover {
  background: #242424;
  border-color: #444;
  color: #ffffff;
}

.tarjeta:active {
  background: #2a2a2a;
  transform: scale(0.98);
}