:root {
  color-scheme: dark;
  --bg: #0b0d12;
  --panel: #161922;
  --panel-2: #1f2330;
  --border: #2a2f3d;
  --text: #e8eaf0;
  --muted: #8b91a5;
  --accent: #6ea8fe;
  --danger: #ff6b6b;
  --ok: #4ade80;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
}

* { box-sizing: border-box; }

body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  min-height: 100vh;
}

.page {
  max-width: 720px;
  margin: 0 auto;
  padding: 24px 16px 48px;
}

.center { text-align: center; }

h1 { font-size: 1.6rem; margin-bottom: 4px; }
.subtitle { color: var(--muted); margin-top: 0; }
.muted { color: var(--muted); font-size: 0.85rem; }
.hint { color: var(--muted); font-size: 0.8rem; margin: 4px 0 0; }

.back-link {
  color: var(--muted);
  text-decoration: none;
  font-size: 0.9rem;
  display: inline-block;
  margin-bottom: 16px;
}

.card {
  background: var(--panel);
  border: 1px solid var(--border);
  border-radius: 16px;
  padding: 32px 24px;
  margin-top: 40px;
}

.choice-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 16px;
  margin-top: 32px;
}
@media (max-width: 480px) {
  .choice-grid { grid-template-columns: 1fr; }
}

.choice-card {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 6px;
  background: var(--panel);
  border: 1px solid var(--border);
  border-radius: 16px;
  padding: 32px 16px;
  text-decoration: none;
  color: var(--text);
}
.choice-icon { font-size: 2.2rem; }
.choice-title { font-weight: 600; }
.choice-desc { color: var(--muted); font-size: 0.85rem; }

.code-input {
  display: block;
  width: 100%;
  font-size: 1.6rem;
  letter-spacing: 0.2em;
  text-align: center;
  text-transform: uppercase;
  padding: 12px;
  margin: 20px 0;
  border-radius: 10px;
  border: 1px solid var(--border);
  background: var(--panel-2);
  color: var(--text);
}

button {
  background: var(--accent);
  color: #0b0d12;
  border: none;
  border-radius: 10px;
  padding: 12px 18px;
  font-size: 1rem;
  font-weight: 600;
  cursor: pointer;
}
button.danger { background: var(--danger); }
button.active { outline: 2px solid var(--accent); }
button:disabled { opacity: 0.6; cursor: default; }

input, select {
  font-size: 1rem;
  padding: 8px 10px;
  border-radius: 8px;
  border: 1px solid var(--border);
  background: var(--panel-2);
  color: var(--text);
}

.error { color: var(--danger); margin-top: 12px; }

.video-wrap {
  position: relative;
  background: #000;
  border-radius: 16px;
  overflow: hidden;
  aspect-ratio: 16 / 9;
}
video {
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: filter 0.2s ease, transform 0.1s ease;
}
video.low-light { filter: brightness(1.7) contrast(1.15) saturate(1.05); }

.mic-level {
  position: absolute;
  bottom: 10px;
  left: 10px;
  right: 10px;
  height: 6px;
  background: rgba(255, 255, 255, 0.15);
  border-radius: 4px;
  overflow: hidden;
}
.mic-level::after {
  content: "";
  display: block;
  height: 100%;
  width: var(--level, 0%);
  background: var(--ok);
  transition: width 0.1s linear;
}
.mic-level.flash::after { background: var(--danger); }

.status-line {
  margin: 10px 0;
  color: var(--muted);
  font-size: 0.9rem;
}

.panel {
  margin-top: 16px;
  background: var(--panel);
  border: 1px solid var(--border);
  border-radius: 16px;
  padding: 16px;
}

.row {
  display: flex;
  align-items: center;
  gap: 10px;
  flex-wrap: wrap;
  margin-bottom: 14px;
}
.row:last-child { margin-bottom: 0; }
.row input[type="range"] { flex: 1; min-width: 120px; }

.sleep-row { justify-content: space-between; }

.room-code-badge {
  font-size: 1.1rem;
  margin-bottom: 14px;
}
.room-code-badge strong {
  letter-spacing: 0.15em;
  color: var(--accent);
}

.stats-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 10px;
  text-align: center;
  padding-top: 8px;
  border-top: 1px solid var(--border);
  margin-top: 4px;
}

.alert-banner {
  background: var(--danger);
  color: #1a0000;
  font-weight: 700;
  text-align: center;
  padding: 12px;
  border-radius: 12px;
  margin-bottom: 12px;
  animation: pulse 1s ease-in-out infinite;
}
@keyframes pulse {
  0%, 100% { opacity: 1; }
  50% { opacity: 0.6; }
}

.auth-overlay {
  position: fixed;
  inset: 0;
  background: rgba(11, 13, 18, 0.96);
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 16px;
  z-index: 1000;
}
.auth-card {
  background: var(--panel);
  border: 1px solid var(--border);
  border-radius: 16px;
  padding: 32px 24px;
  max-width: 320px;
  width: 100%;
  text-align: center;
}
.auth-card input {
  width: 100%;
  margin: 16px 0;
  text-align: center;
}
.auth-card button { width: 100%; }