:root {
  color-scheme: dark;
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  min-height: 100vh;
  display: grid;
  place-items: center;
  font-family: "Segoe UI", Tahoma, Geneva, Verdana, sans-serif;
  background: radial-gradient(circle at top, #1f2a5a 0%, #0e1022 50%, #06070f 100%);
  color: #e9f4ff;
}

.clock-app {
  width: min(92vw, 640px);
  text-align: center;
  padding: 2.25rem 1.5rem;
  border-radius: 1rem;
  background: linear-gradient(145deg, rgba(14, 17, 34, 0.95), rgba(8, 10, 19, 0.95));
  box-shadow: 0 0 40px rgba(0, 204, 255, 0.15), inset 0 0 1px rgba(255, 255, 255, 0.3);
}

h1 {
  margin: 0 0 1rem;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  font-size: clamp(1rem, 2.5vw, 1.4rem);
  color: #9fd3ff;
}

.led-display {
  margin: 0;
  font-family: "Courier New", monospace;
  font-size: clamp(2.6rem, 10vw, 5rem);
  letter-spacing: 0.16em;
  color: #56ffcd;
  text-shadow:
    0 0 8px rgba(86, 255, 205, 0.85),
    0 0 20px rgba(86, 255, 205, 0.6),
    0 0 34px rgba(12, 230, 255, 0.45);
}

.toggle {
  margin-top: 1.25rem;
  display: inline-flex;
  align-items: center;
  gap: 0.6rem;
  color: #cbe6ff;
  cursor: pointer;
}

.toggle input {
  width: 1rem;
  height: 1rem;
  accent-color: #56ffcd;
}