body {
  margin: 0;
  height: 100vh;
  display: flex;
  justify-content: center;
  align-items: center;
  background: #f3f3f3;
  font-family: 'Poppins', sans-serif;
  transition: background 0.3s, color 0.3s;
}

.clock-container {
  text-align: center;
}

#clock {
  font-size: 80px;
  color: #222;
}

button {
  margin-top: 20px;
  padding: 10px 20px;
  border: none;
  border-radius: 8px;
  background: #222;
  color: white;
  cursor: pointer;
}

button:hover {
  background: #444;
}

/* Dark mode */
.dark {
  background: #222;
  color: white;
}

.dark #clock {
  color: #00ffcc;
}

.dark button {
  background: white;
  color: #222;
}