body {
  font-family: "Segoe UI", Roboto, Arial, sans-serif;
  background: radial-gradient(circle at center, #eef2ff 0%, #c7d2fe 100%);
  height: 100vh;
  margin: 0;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  color: #1e3a8a;
}

h1 {
  font-size: 2rem;
  margin-bottom: 1.5rem;
  text-align: center;
}

.contador {
  font-size: 2.3rem;
  font-weight: bold;
  color: #007acc;
  margin-bottom: 1.5rem;
  transition: transform 0.4s ease, color 0.4s ease;
}

.contador.reseteado {
  transform: scale(1.25);
  color: #00a800;
}

.btn {
  background-color: #007acc;
  color: white;
  border: none;
  border-radius: 10px;
  padding: 0.8rem 1.2rem;
  cursor: pointer;
  font-size: 1rem;
  transition: background-color 0.2s ease, transform 0.2s ease;
}

.btn:hover {
  background-color: #005fa3;
  transform: scale(1.05);
}

.btn:disabled {
  background-color: #999;
  cursor: not-allowed;
}

.mensaje {
  margin-top: 1rem;
  font-size: 0.9rem;
  color: #333;
  text-align: center;
}

footer {
  position: fixed;
  bottom: 10px;
  width: 100%;
  text-align: center;
  font-size: 0.85rem;
  color: #4b5563;
  text-align: center;
}

footer uve {
  font-weight: bold;
  color: #007acc;
}