:root {
  --bg-light: #f0f0f0;
  --text-light: #333;
  --bg-dark:  #222;
  --text-dark: #eee;
  --accent:    #0066ff;
}

body {
  margin: 0;
  font-family: 'Segoe UI', sans-serif;
  display: flex;
  align-items: center;
  justify-content: center;
  height: 100vh;
  background-color: var(--bg-light);
  color: var(--text-light);
  transition: background-color 0.3s, color 0.3s;
}

.container {
  text-align: center;
  padding: 2rem;
  border-radius: 8px;
  box-shadow: 0 4px 12px rgba(0,0,0,0.1);
}

#clock {
  font-size: 3rem;
  letter-spacing: 2px;
  margin: 1rem 0;
}

.toggle {
  display: inline-flex;
  align-items: center;
  cursor: pointer;
  user-select: none;
}

.toggle input {
  display: none;
}

.slider {
  position: relative;
  width: 50px;
  height: 24px;
  background: #ccc;
  border-radius: 12px;
  margin-right: .5rem;
  transition: background 0.3s;
}

.slider::before {
  content: "";
  position: absolute;
  top: 2px;
  left: 2px;
  width: 20px;
  height: 20px;
  background: white;
  border-radius: 50%;
  transition: transform 0.3s;
}

input:checked + .slider {
  background: var(--accent);
}

input:checked + .slider::before {
  transform: translateX(26px);
}

.label-text {
  font-size: .9rem;
}