* {
  box-sizing: border-box;
}

html, body {
  height: 100%;
  margin: 0;
}

body {
  background: #0b0d12;
  color: #e8ebf1;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  display: flex;
  align-items: center;
  justify-content: center;
  overflow: hidden;
}

#app {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 0.75rem;
  padding: 2rem;
  width: 100%;
}

.status {
  font-size: 0.8rem;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: #6b7280;
  height: 1.2em;
  transition: opacity 0.4s ease;
}

.status.synced {
  color: #4ade80;
}

.status.faded {
  opacity: 0.3;
}

.clock {
  font-family: "SF Mono", "Cascadia Code", Consolas, "Roboto Mono", monospace;
  font-variant-numeric: tabular-nums;
  font-weight: 600;
  font-size: clamp(3rem, 14vw, 10rem);
  line-height: 1;
  display: flex;
  align-items: baseline;
  white-space: nowrap;
}

.ms {
  font-size: 0.4em;
  color: #7dd3fc;
  width: 4.6ch;
  display: inline-block;
  text-align: left;
  margin-right: 0.15em;
}

.period {
  font-size: 0.3em;
  color: #9ca3af;
  margin-left: 0.3em;
  letter-spacing: 0.05em;
}

.date {
  font-size: clamp(0.9rem, 2.2vw, 1.3rem);
  color: #9ca3af;
}

.zone {
  font-size: 0.8rem;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: #4b5563;
  margin-top: -0.25rem;
}

.controls {
  display: flex;
  align-items: center;
  gap: 1.5rem;
  margin-top: 1.5rem;
}

.toggle {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  font-size: 0.9rem;
  color: #9ca3af;
  cursor: pointer;
  user-select: none;
}

.toggle input {
  width: 1.1rem;
  height: 1.1rem;
  accent-color: #7dd3fc;
  cursor: pointer;
}

.icon-btn {
  background: transparent;
  border: 1px solid #2a2e37;
  color: #9ca3af;
  border-radius: 0.5rem;
  padding: 0.5rem;
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  transition: background 0.15s ease, color 0.15s ease, border-color 0.15s ease;
}

.icon-btn:hover {
  background: #161923;
  color: #e8ebf1;
  border-color: #3a3f4b;
}

:fullscreen #app,
:-webkit-full-screen #app {
  transform: scale(1.05);
}

.alert-overlay {
  position: fixed;
  inset: 0;
  z-index: 1000;
  display: none;
  align-items: center;
  justify-content: center;
  text-align: center;
  padding: 2rem;
}

.alert-overlay.active {
  display: flex;
  animation: flash-strobe 0.5s steps(1, end) infinite;
}

.alert-overlay.yellow {
  --alert-color: #f5c400;
}

.alert-overlay.green {
  --alert-color: #22c55e;
}

@keyframes flash-strobe {
  0%, 49% {
    background-color: var(--alert-color);
  }
  50%, 100% {
    background-color: #05060a;
  }
}

.alert-text {
  font-size: clamp(2.5rem, 9vw, 6.5rem);
  font-weight: 900;
  letter-spacing: 0.05em;
  text-transform: uppercase;
  color: #fff;
  text-shadow: 0 0 4px rgba(0, 0, 0, 0.9), 0 0 16px rgba(0, 0, 0, 0.9);
}