:root {
  color-scheme: dark;
  --bg: #060708;
  --panel: rgba(255, 255, 255, 0.04);
  --border: rgba(255, 255, 255, 0.1);
  --text: #f5f7fb;
  --muted: rgba(245, 247, 251, 0.7);
  --accent: #9ef0ff;
}

* {
  box-sizing: border-box;
}

html,
body {
  margin: 0;
  min-height: 100%;
  background:
    radial-gradient(circle at top, rgba(158, 240, 255, 0.14), transparent 34%),
    radial-gradient(circle at bottom, rgba(255, 180, 120, 0.1), transparent 28%),
    var(--bg);
  color: var(--text);
  font-family: "SF Pro Display", "Segoe UI", sans-serif;
}

body {
  min-height: 100vh;
  display: grid;
  place-items: center;
  padding: 24px;
}

.app-shell {
  width: min(100%, 560px);
  text-align: center;
  padding: 32px 24px;
  border: 1px solid var(--border);
  border-radius: 28px;
  background: var(--panel);
  backdrop-filter: blur(18px);
  box-shadow: 0 18px 60px rgba(0, 0, 0, 0.35);
}

.eyebrow {
  margin: 0 0 12px;
  text-transform: uppercase;
  letter-spacing: 0.24em;
  font-size: 12px;
  color: var(--accent);
}

.seconds {
  font-size: clamp(96px, 30vw, 240px);
  line-height: 0.9;
  font-weight: 700;
  font-variant-numeric: tabular-nums;
  letter-spacing: -0.06em;
}

.status,
.note {
  margin: 16px 0 0;
  color: var(--muted);
}

.status {
  font-size: 16px;
}

.note {
  font-size: 13px;
}

.start-overlay {
  position: fixed;
  inset: 0;
  border: 0;
  display: none;
  padding: 32px;
  background: rgba(6, 7, 8, 0.84);
  color: var(--text);
  text-align: center;
  cursor: pointer;
  backdrop-filter: blur(18px);
}

.start-overlay.is-visible {
  display: grid;
  place-items: center;
  gap: 16px;
}

.overlay-title {
  display: block;
  font-size: clamp(32px, 8vw, 48px);
  font-weight: 700;
}

.overlay-copy {
  display: block;
  max-width: 480px;
  font-size: 16px;
  color: var(--muted);
}